Examples with solutions for Solving an Equation by Multiplication/ Division: Using fractions

Exercise #1

Find the value of the parameter X

13x=19 \frac{1}{3}x=\frac{1}{9}

Video Solution

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Identify the given fraction equation.
  • Multiply both sides of the equation by the reciprocal of the coefficient of x x .
  • Simplify to isolate x x .

Now, let's work through these steps:
Step 1: The problem gives us the equation 13x=19 \frac{1}{3} x = \frac{1}{9} .
Step 2: We multiply both sides by 3 to eliminate the fraction on the left side:

3×13x=3×19 3 \times \frac{1}{3} x = 3 \times \frac{1}{9}

Step 3: Simplifying both sides results in:

x=39 x = \frac{3}{9}

Further simplification of 39\frac{3}{9} yields:

x=13 x = \frac{1}{3}

Therefore, the solution to the problem is 13 \frac{1}{3} .

Answer

13 \frac{1}{3}

Exercise #2

y5=25 \frac{-y}{5}=-25

Video Solution

Step-by-Step Solution

We begin by multiplying the simple fraction by y:

15×y=25 \frac{-1}{5}\times y=-25

We then reduce both terms by 15 -\frac{1}{5}

y=2515 y=\frac{-25}{-\frac{1}{5}}

Finally we multiply the fraction by negative 5:

y=25×(5)=125 y=-25\times(-5)=125

Answer

y=125 y=125

Exercise #3

Solve the equation

312y=21 3\frac{1}{2}\cdot y=21

Video Solution

Step-by-Step Solution

To solve the equation 312y=21 3\frac{1}{2} \cdot y = 21 , we'll follow these steps:

  • Convert the mixed number to an improper fraction.
  • Divide both sides of the equation by the coefficient of y y .

Let's analyze these steps in detail:

Step 1: Convert the mixed number to an improper fraction.
The coefficient of y y is 312 3\frac{1}{2} . Converting to an improper fraction, we have:

312=72 3\frac{1}{2} = \frac{7}{2}

Step 2: Divide both sides of the equation by 72 \frac{7}{2} .
The equation becomes:

72y=21 \frac{7}{2} \cdot y = 21

To isolate y y , divide both sides by 72 \frac{7}{2} :

y=21÷72 y = 21 \div \frac{7}{2}

Dividing by a fraction is equivalent to multiplying by its reciprocal, so:

y=2127 y = 21 \cdot \frac{2}{7}

Carrying out the multiplication, we calculate:

y=2127=427 y = \frac{21 \cdot 2}{7} = \frac{42}{7}

Dividing the numerator by the denominator gives us:

y=6 y = 6

Thus, the solution to the equation is y=6 y = 6 .

Answer

y=6 y=6

Exercise #4

3b=76 3b=\frac{7}{6}

Video Solution

Step-by-Step Solution

To solve the equation 3b=76 3b = \frac{7}{6} for the variable b b , we will perform the following steps:

  • Step 1: Identify the equation. The given equation is 3b=76 3b = \frac{7}{6} .
  • Step 2: Isolate the variable. Divide both sides by 3 to solve for b b .

When we divide both sides of the equation by 3, we obtain:

b=763 b = \frac{\frac{7}{6}}{3}

Step 3: Simplify the expression. Dividing a fraction by an integer is equivalent to multiplying the denominator of the fraction by that integer:

b=76×3 b = \frac{7}{6 \times 3}

The denominator becomes:

b=718 b = \frac{7}{18}

Thus, the solution to the equation is b=718 b = \frac{7}{18} .

This matches the correct answer choice among the given options.

Therefore, the value of b b is b=718 b = \frac{7}{18} .

Answer

b=718 b=\frac{7}{18}

Exercise #5

Solve for X:

15x4=6 \frac{1}{5}x-4=6

Video Solution

Step-by-Step Solution

To solve the equation 15x4=6\frac{1}{5}x - 4 = 6, we will follow these steps:

  • Step 1: Add 4 to both sides of the equation to eliminate the subtraction and isolate the fractional term.
  • Step 2: Multiply both sides by 5 to clear the fraction and solve for x x .

Let's apply these steps to solve the equation:

Step 1: Add 4 to both sides:
15x4+4=6+4 \frac{1}{5}x - 4 + 4 = 6 + 4
This simplifies to:
15x=10 \frac{1}{5}x = 10

Step 2: Multiply both sides by 5 to solve for x x :
5×15x=10×5 5 \times \frac{1}{5}x = 10 \times 5
This simplifies to:
x=50 x = 50

Therefore, the solution to the equation is x=50 x = 50 .

Answer

50

Exercise #6

Solve for X:

28x3=7 \frac{2}{8}x-3=7

Video Solution

Step-by-Step Solution

To solve the equation 28x3=7 \frac{2}{8}x - 3 = 7 , we'll follow these steps:

  • Step 1: Simplify the fraction. The coefficient 28 \frac{2}{8} simplifies to 14 \frac{1}{4} .
  • Step 2: Eliminate the constant term by adding 3 to both sides of the equation.
  • Step 3: Solve for x x by removing the coefficient of x x using division.

Let's solve the equation step-by-step:

Step 1: Simplify the equation:
The equation 28x3=7 \frac{2}{8}x - 3 = 7 simplifies to 14x3=7 \frac{1}{4}x - 3 = 7 .

Step 2: Eliminate the constant term:
Add 3 to both sides to isolate the term involving x x :

14x3+3=7+3\frac{1}{4}x - 3 + 3 = 7 + 3

This simplifies to:

14x=10\frac{1}{4}x = 10

Step 3: Solve for x x :
Multiply both sides by the reciprocal of 14 \frac{1}{4} to solve for x x :

414x=4104 \cdot \frac{1}{4}x = 4 \cdot 10

This simplifies to:

x=40x = 40

Therefore, the solution to the equation is x=40 x = 40 .

Answer

40

Exercise #7

3x4=16 \frac{3x}{4}=16

Video Solution

Step-by-Step Solution

To solve the equation 3x4=16\frac{3x}{4} = 16, we will eliminate the fraction by multiplying both sides by 4.

  • Step 1: Multiply both sides by 4:
    (3x4)×4=16×4\left(\frac{3x}{4}\right) \times 4 = 16 \times 4
  • Step 2: Simplify:
    3x=643x = 64
  • Step 3: Solve for xx by dividing both sides by 3:
    x=643x = \frac{64}{3}
  • Step 4: Simplify the fraction to a mixed number:
    x=2113x = 21\frac{1}{3}

Therefore, the solution to the equation 3x4=16\frac{3x}{4} = 16 is x=2113 x = 21\frac{1}{3} .

Answer

x=2113 x=21\frac{1}{3}

Exercise #8

x4+2x18=0 \frac{x}{4}+2x-18=0

x=? x=\text{?}

Video Solution

Step-by-Step Solution

To solve the equation x4+2x18=0\frac{x}{4} + 2x - 18 = 0, we proceed as follows:

  • Step 1: Eliminate the fraction by multiplying the entire equation by 4:
    (4)(x4+2x18)=(4)(0)(4) \Big(\frac{x}{4} + 2x - 18\Big) = (4)(0)
  • Step 2: Distribute and simplify:
    x+8x72=0x + 8x - 72 = 0
  • Step 3: Combine like terms:
    9x72=09x - 72 = 0
  • Step 4: Isolate 9x9x by adding 72 to both sides:
    9x=729x = 72
  • Step 5: Solve for xx by dividing both sides by 9:
    x=729x = \frac{72}{9}
  • Step 6: Simplify the division:
    x=8x = 8

Thus, the solution to the problem is x=8x = 8.

Answer

8

Exercise #9

Solve for X:

x+43=78 \frac{x+4}{3}=\frac{7}{8}

Video Solution

Step-by-Step Solution

First, we cross multiply:

8×(x+4)=3×7 8\times(x+4)=3\times7

We multiply the right section and expand the parenthesis, multiplying each of the terms by 8:

8x+32=21 8x+32=21

We rearrange the equation remembering change the plus and minus signs accordingly:

8x=2132 8x=21-32
Solve the subtraction exercise on the right side and divide by 8:

8x=11 8x=-11

8x8=118 \frac{8x}{8}=-\frac{11}{8}

Convert the simple fraction into a mixed fraction:

x=138 x=-1\frac{3}{8}

Answer

138 -1\frac{3}{8}

Exercise #10

Find the value of the parameter X

13x+56=16 \frac{1}{3}x+\frac{5}{6}=-\frac{1}{6}

Video Solution

Step-by-Step Solution

First, we will arrange the equation so that we have variables on one side and numbers on the other side.

Therefore, we will move 56 \frac{5}{6} to the other side, and we will get

13x=1656 \frac{1}{3}x=-\frac{1}{6}-\frac{5}{6}

Note that the two fractions on the right side share the same denominator, so you can subtract them:

13x=66 \frac{1}{3}x=-\frac{6}{6}

Observe the minus sign on the right side!

13x=1 \frac{1}{3}x=-1

Now, we will try to get rid of the denominator, we will do this by multiplying the entire exercise by the denominator (that is, all terms on both sides of the equation):

1x=3 1x=-3

x=3 x=-3

Answer

-3

Exercise #11

Find the value of the parameter X

23x+14=34 \frac{2}{3}x+\frac{1}{4}=\frac{3}{4}

Video Solution

Step-by-Step Solution

Let's proceed with solving the equation step by step:

  1. Start with the equation 23x+14=34 \frac{2}{3}x + \frac{1}{4} = \frac{3}{4} .

  2. Subtract 14 \frac{1}{4} from both sides to remove the constant term on the left:
    23x+1414=3414 \frac{2}{3}x + \frac{1}{4} - \frac{1}{4} = \frac{3}{4} - \frac{1}{4} .

  3. This simplifies to: 23x=3414 \frac{2}{3}x = \frac{3}{4} - \frac{1}{4} .

  4. Perform the subtraction on the right-hand side:
    23x=24=12 \frac{2}{3}x = \frac{2}{4} = \frac{1}{2} .

  5. Now solve for x x by dividing both sides of the equation by 23 \frac{2}{3} :
    x=12÷23 x = \frac{1}{2} \div \frac{2}{3} .

  6. Dividing by a fraction is the same as multiplying by its reciprocal:
    x=12×32 x = \frac{1}{2} \times \frac{3}{2} .

  7. Simplify the multiplication:
    x=34 x = \frac{3}{4} .

Therefore, the value of the parameter x x is 34\frac{3}{4}.

Answer

34 \frac{3}{4}

Exercise #12

Solve for X:
23x46=13 \frac{2}{3}x-\frac{4}{6}=\frac{1}{3}

Video Solution

Step-by-Step Solution

Let's solve the equation 23x46=13 \frac{2}{3}x - \frac{4}{6} = \frac{1}{3} .

Step 1: Simplify the fractions.

  • The term 46\frac{4}{6} is equivalent to 23\frac{2}{3} after simplification.

Now, the equation can be rewritten as:

23x23=13\frac{2}{3}x - \frac{2}{3} = \frac{1}{3}

Step 2: Add 23\frac{2}{3} to both sides to isolate the term with x x .

23x=13+23\frac{2}{3}x = \frac{1}{3} + \frac{2}{3}

Simplify the right side:

23x=33\frac{2}{3}x = \frac{3}{3}

33=1\frac{3}{3} = 1

So the equation becomes:

23x=1\frac{2}{3}x = 1

Step 3: Solve for x x by multiplying both sides by the reciprocal of 23\frac{2}{3}.

Multiply both sides by 32\frac{3}{2}:

x=1×32x = 1 \times \frac{3}{2}

Thus, the solution is:

x=32x = \frac{3}{2}

The solution to the problem is x=32 x = \frac{3}{2} .

Answer

32 \frac{3}{2}

Exercise #13

Find the value of the parameter X

3x19=89 3x-\frac{1}{9}=\frac{8}{9}

Video Solution

Step-by-Step Solution

To find the value of xx in the given equation, we will perform the following steps:

  • Step 1: Start with the equation given: 3x19=893x - \frac{1}{9} = \frac{8}{9}.
  • Step 2: To eliminate the constant 19-\frac{1}{9} on the left, add 19\frac{1}{9} to both sides:

3x19+19=89+193x - \frac{1}{9} + \frac{1}{9} = \frac{8}{9} + \frac{1}{9}

This simplifies to:

3x=89+193x = \frac{8}{9} + \frac{1}{9}

Combine the fractions on the right side:

89+19=99=1\frac{8}{9} + \frac{1}{9} = \frac{9}{9} = 1

So, now we have:

3x=13x = 1

  • Step 3: Divide both sides by 3 to solve for xx:

x=13x = \frac{1}{3}

Thus, the solution to the equation is:

x=13x = \frac{1}{3}

Answer

13 \frac{1}{3}

Exercise #14

Solve for X:

78x=25 \frac{7}{8}x=\frac{2}{5}

Video Solution

Step-by-Step Solution

To solve for x x in the equation 78x=25 \frac{7}{8}x = \frac{2}{5} , we will follow these steps:

  • Multiply both sides of the equation by the reciprocal of 78\frac{7}{8}, which is 87\frac{8}{7}.
  • Simplify the resulting expression to find the value of x x .

Let's work through these steps:

First, multiply both sides by 87\frac{8}{7} to isolate x x on the left side.

87×78x=87×25 \frac{8}{7} \times \frac{7}{8}x = \frac{8}{7} \times \frac{2}{5}

This simplifies to:

x=87×25 x = \frac{8}{7} \times \frac{2}{5}

Now, perform the multiplication of the fractions:

x=8×27×5=1635 x = \frac{8 \times 2}{7 \times 5} = \frac{16}{35}

Thus, the value of x x is 1635\frac{16}{35}.

Answer

1635 \frac{16}{35}

Exercise #15

12y+4y+53=2y 12y+4y+5-3=2y

y=? y=\text{?}

Video Solution

Step-by-Step Solution

To solve the equation 12y+4y+53=2y12y + 4y + 5 - 3 = 2y, we'll follow these steps:

  • **Step 1**: Simplify the left side of the equation by combining like terms: 12y+4y=16y12y + 4y = 16y.
  • **Step 2**: Replace that in the equation: 16y+53=2y16y + 5 - 3 = 2y. Simplify further to 16y+2=2y16y + 2 = 2y.
  • **Step 3**: Isolate yy by getting all the terms involving yy on one side. Subtract 2y2y from both sides, yielding: 16y2y=216y - 2y = -2.
  • **Step 4**: This simplifies to 14y=214y = -2.
  • **Step 5**: Divide each side by 14 to solve for yy: y=214y = \frac{-2}{14}.
  • **Step 6**: Simplify the fraction: y=17y = -\frac{1}{7}.

Therefore, the solution to the problem is y=17 y = -\frac{1}{7} .

Answer

17 -\frac{1}{7}

Exercise #16

Solve for X:

17.518x5.5x=19.2+14125x 17.5-18x-5.5x=19.2+14\frac{1}{2}-5x

Video Solution

Step-by-Step Solution

To solve the equation 17.518x5.5x=19.2+14125x 17.5 - 18x - 5.5x = 19.2 + 14\frac{1}{2} - 5x , follow these steps:

Step 1: Combine like terms on both sides of the equation.

  • On the left side, combine 18x5.5x -18x - 5.5x , which simplifies to 23.5x -23.5x .
  • On the right side, simplify 19.2+14.55x 19.2 + 14.5 - 5x . The fraction 1412 14\frac{1}{2} is converted to decimal form as 14.5 14.5 , giving 19.2+14.5=33.7 19.2 + 14.5 = 33.7 .

Step 2: Rewrite the equation with the simplified terms:

17.523.5x=33.75x 17.5 - 23.5x = 33.7 - 5x .

Step 3: Get all terms involving x x on one side of the equation and constant terms on the other.

  • Add 5x 5x to both sides to move all x x related terms to the left:
  • 17.523.5x+5x=33.7 17.5 - 23.5x + 5x = 33.7
  • This further simplifies to 17.518.5x=33.7 17.5 - 18.5x = 33.7 .

    Step 4: Isolate the term with x x by subtracting 17.5 17.5 from both sides:

    18.5x=33.717.5 -18.5x = 33.7 - 17.5 .

    The right side evaluates to 16.2 16.2 .

    Thus, we have 18.5x=16.2 -18.5x = 16.2 .

    Step 5: Solve for x x by dividing both sides by 18.5-18.5:

    x=16.218.50.8757 x = \frac{16.2}{-18.5} \approx -0.8757 .

    Rounding 0.8757 -0.8757 to two decimal places gives x=0.87 x = -0.87 .

    Therefore, the solution to the equation is x=0.87 x = -0.87 .

    This corresponds to option 2 in the given choices.

Answer

0.87 -0.87

Exercise #17

Solve for X:

22x12+1612=14.5x12 22x-\frac{1}{2}+16\frac{1}{2}=14.5x-12

Video Solution

Step-by-Step Solution

To solve the equation 22x12+1612=14.5x12 22x - \frac{1}{2} + 16\frac{1}{2} = 14.5x - 12 , we will follow these steps:
1. Combine like terms on both sides of the equation.
2. Isolate the variable x x .
3. Solve for x x .

Let's start by simplifying each side:

  • Simplify the left-hand side: 22x12+1612 22x - \frac{1}{2} + 16\frac{1}{2} .

The term 1612 16\frac{1}{2} is equivalent to 16.5 16.5 , so the left-hand side becomes:
22x0.5+16.5=22x+16 22x - 0.5 + 16.5 = 22x + 16.

  • Now simplify the right-hand side: 14.5x12 14.5x - 12 .

The right-hand side remains as 14.5x12 14.5x - 12 .

Now, let's collect like terms. Move the term involving x x from the right-hand side to the left:

  • Subtract 14.5x 14.5x from both sides:
    22x+1614.5x=12 22x + 16 - 14.5x = -12

This simplifies to:
7.5x+16=12 7.5x + 16 = -12 .

Next, isolate the constant term. Subtract 16 from both sides:

  • 7.5x+1616=1216 7.5x + 16 - 16 = -12 - 16

This simplifies to:
7.5x=28 7.5x = -28 .

Finally, solve for x x by dividing both sides by 7.5:

  • x=287.5 x = \frac{-28}{7.5}

Calculating the fraction gives approximately:
x3.73 x \approx -3.73 .

Therefore, the solution to the problem is x=3.73 x = -3.73 .

Answer

3.73 -3.73

Exercise #18

Solve for X:

16x13=13 \frac{1}{6}x-\frac{1}{3}=\frac{1}{3}

Video Solution

Step-by-Step Solution

To solve the equation 16x13=13 \frac{1}{6}x - \frac{1}{3} = \frac{1}{3} , we will take the following steps:

  • Step 1: Eliminate fractions by multiplying the entire equation by the least common multiple of the denominators 6 6 .
  • Step 2: Simplify the resulting equation.
  • Step 3: Isolate the variable x x .

Let's proceed with the solution:

Step 1: Multiply the entire equation by 6 6 to clear fractions:
6(16x13)=6×13 6 \left(\frac{1}{6}x - \frac{1}{3}\right) = 6 \times \frac{1}{3}

Step 2: Simplify:
x2=2 x - 2 = 2

Step 3: Solve for x x by adding 2 2 to both sides:
x=2+2 x = 2 + 2

Therefore, x=4 x = 4 .

Answer

4 4

Exercise #19

Solve for X:

25x=38 \frac{2}{5}x=\frac{3}{8}

Video Solution

Step-by-Step Solution

To solve the equation 25x=38 \frac{2}{5}x = \frac{3}{8} , we need to isolate xx. We can achieve this by multiplying both sides by the reciprocal of 25\frac{2}{5}.

Step 1: Multiply both sides by 52\frac{5}{2}, which is the reciprocal of 25\frac{2}{5}:

52×25x=52×38 \frac{5}{2} \times \frac{2}{5}x = \frac{5}{2} \times \frac{3}{8}

Step 2: Simplify the left side. The 52\frac{5}{2} and 25\frac{2}{5} cancel each other out:

x=5×32×8 x = \frac{5 \times 3}{2 \times 8}

Step 3: Simplify the right side by multiplying the numerators and denominators:

x=1516 x = \frac{15}{16}

Therefore, the solution to the equation is 1516\boxed{\frac{15}{16}}, which matches choice 3.

Answer

1516 \frac{15}{16}

Exercise #20

Solve for X:
49+35x=43 \frac{4}{9}+\frac{3}{5}x=\frac{4}{3}

Video Solution

Step-by-Step Solution

To solve the equation 49+35x=43 \frac{4}{9} + \frac{3}{5}x = \frac{4}{3} , we will follow these steps:

  • Step 1: Subtract 49 \frac{4}{9} from both sides to isolate the term involving x x .
  • Step 2: Divide by the coefficient of x x to solve for x x .

Step 1: Subtract 49 \frac{4}{9} from both sides:

35x=4349 \frac{3}{5}x = \frac{4}{3} - \frac{4}{9}

To subtract these fractions, find a common denominator. The least common denominator for 3 and 9 is 9. Rewrite 43 \frac{4}{3} as 129 \frac{12}{9} (since 4×3=12 4 \times 3 = 12), resulting in:

35x=12949=89 \frac{3}{5}x = \frac{12}{9} - \frac{4}{9} = \frac{8}{9}

Step 2: Divide both sides by 35 \frac{3}{5} to solve for x x :

x=89÷35=89×53 x = \frac{8}{9} \div \frac{3}{5} = \frac{8}{9} \times \frac{5}{3}

Multiply the fractions. The result is:

x=8×59×3=4027 x = \frac{8 \times 5}{9 \times 3} = \frac{40}{27}

Thus, the solution to the equation is x=4027 x = \frac{40}{27} .

Answer

4027 \frac{40}{27}