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

Exercise #1

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 #2

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 #3

Solve for x:

8x45=2x+24 \frac{8x-4}{5}=\frac{2x+2}{4}

Video Solution

Step-by-Step Solution

To get rid of the fraction mechanics, we will cross multiply between the sides:

4(8x4)=5(2x+2) 4(8x-4)=5(2x+2)

We expand the parentheses by multiplying the outer element by each of the elements inside the parentheses:

32x16=10x+10 32x-16=10x+10

We arrange the sides accordingly so that the elements with the X are on the left side and those without the X are on the right side:

32x10x=10+16 32x-10x=10+16

We calculate the elements:

22x=26 22x=26

We divide the two sections by 22:

22x22=2622 \frac{22x}{22}=\frac{26}{22}

x=2622 x=\frac{26}{22}

Answer

2622 \frac{26}{22}

Exercise #4

4=3y 4=3y

Video Solution

Answer

y=113 y=1\frac{1}{3}

Exercise #5

6x=12.6 6x=-12.6

Video Solution

Answer

x=2.1 x=-2.1

Exercise #6

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

Video Solution

Answer

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

Exercise #7

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

Video Solution

Answer

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

Exercise #8

Solve for X:

x+23=45 \frac{x+2}{3}=\frac{4}{5}

Video Solution

Answer

25 \frac{2}{5}

Exercise #9

Solve for X:

x418=79 \frac{x-4}{18}=\frac{7}{9}

Video Solution

Answer

18 18

Exercise #10

Solve for X:

x57=211 \frac{x-5}{7}=\frac{2}{11}

Video Solution

Answer

6911 \frac{69}{11}

Exercise #11

4x6.9=2.2x+5 4x-6.9=2.2x+5

Video Solution

Answer

x=61118 x=6\frac{11}{18}

Exercise #12

70=412b 70=4\frac{1}{2}b

Video Solution

Answer

b=1559 b=15\frac{5}{9}

Exercise #13

a6=67 \frac{a}{6}=\frac{6}{7}

Video Solution

Answer

a=517 a=5\frac{1}{7}

Exercise #14

Solve for X:

58x=32x \frac{5}{8-x}=\frac{3}{2x}

Video Solution

Answer

2413 \frac{24}{13}

Exercise #15

Solve for X:

5x8=34x \frac{5}{x-8}=\frac{3}{4x}

Video Solution

Answer

2417 \frac{-24}{17}

Exercise #16

Lionel buys x x packs of paper.

The price of each pack is 4.5andhepaysatotalof4.5 and he pays a total of 45.

Calculate x x .

Video Solution

Answer

x=10 x=10

Exercise #17

Solve for X:

5x8=3+x2 \frac{5-x}{8}=\frac{3+x}{2}

Video Solution

Answer

1410 \frac{-14}{10}

Exercise #18

Solve for X:

8+x3=x+49 \frac{-8+x}{3}=\frac{x+4}{9}

Video Solution

Answer

14 14

Exercise #19

1 kg of tomatoes costs 2.8.<br><br>Maggiebuys2kgoftomatoesand0.6kgofcucumbers,costingatotalof2.8.<br><br>Maggie buys 2 kg of tomatoes and 0.6 kg of cucumbers, costing a total of 7.1.

Express the value per kg of cucumbers in terms of x x (in dollars).

Video Solution

Answer

x=2.5 x=2.5