Multiplication of Decimal Fractions: Multiplication by tenths or hundredths

Examples with solutions for Multiplication of Decimal Fractions: Multiplication by tenths or hundredths

Exercise #1

0.1×0.004= 0.1\times0.004=

Video Solution

Step-by-Step Solution

To solve this problem, we'll multiply the decimals as follows:

  • Step 1: Multiply the whole numbers 1 and 4. This gives us 4.
  • Step 2: Count the total number of decimal places in the factors. 0.10.1 has 1 decimal place, and 0.0040.004 has 3 decimal places.
  • Step 3: In the final answer, place the decimal point to ensure our product has 1+3=41 + 3 = 4 decimal places.

Now, let's apply these steps:

First, multiply 1 by 4 to get 4. Then place the decimal in the product so it has 4 decimal places: 0.00040.0004.

Therefore, the solution to the problem is 0.00040.0004.

Answer

0.0004 0.0004

Exercise #2

0.1×0.35= 0.1\times0.35=

Video Solution

Step-by-Step Solution

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

  • Step 1: Convert the decimal numbers into a form that is easier to multiply.
  • Step 2: Multiply the numbers as if they were whole numbers.
  • Step 3: Adjust the product by placing the decimal point correctly.

Now, let's work through each step:

Step 1: Convert the decimals 0.10.1 and 0.350.35 into whole number expressions:

  • 0.10.1 can be thought of as 110\frac{1}{10}.
  • 0.350.35 can be thought of as 35100\frac{35}{100}.

Step 2: Multiply as whole numbers: Multiply 11 and 3535 to obtain 3535.

Step 3: Adjust the decimal point:

  • 0.10.1 has 1 decimal place.
  • 0.350.35 has 2 decimal places.
Thus, their product should have 1+2=31 + 2 = 3 decimal places.

Therefore, the product of 0.10.1 and 0.350.35 is 0.0350.035.

Looking at the choices provided:

  • Choice 1: 0.350.35 is incorrect as it does not consider the decimal adjustment.
  • Choice 2: 0.0350.035 is correct.
  • Choice 3: 0.3500.350 is incorrect as it has an extra zero and maintains the incorrect placement of the decimal point.
  • Choice 4: 0.3100.310 is incorrect as it does not correspond with the straightforward multiplication of the operands.

Thus, the correct choice is 0.0350.035.

Answer

0.035 0.035

Exercise #3

0.1×0.5= 0.1\times0.5=

Video Solution

Step-by-Step Solution

To solve this problem, we'll multiply the decimal numbers 0.10.1 and 0.50.5, following these steps:

  • Step 1: Treat each number as if it were a whole number and multiply: 1×5=51 \times 5 = 5.
  • Step 2: Count the decimal places in both factors. The number 0.10.1 has one decimal place, and 0.50.5 also has one decimal place.
  • Step 3: The total number of decimal places in the product should be the sum of the decimal places in the factors, which is 1+1=21 + 1 = 2.
  • Step 4: Place the decimal point in the product 55, resulting in 0.050.05, to ensure it has two decimal places.

Therefore, the product of 0.10.1 and 0.50.5 is 0.050.05.

Answer

0.05 0.05

Exercise #4

0.1×0.999= 0.1\times0.999=

Video Solution

Step-by-Step Solution

To solve 0.1×0.999 0.1 \times 0.999 , we need to follow these steps carefully:

  • Step 1: Treat the numbers as integers and multiply them. Ignoring the decimal points temporarily, multiply 1 1 by 999 999 :
    1×999=999\quad 1 \times 999 = 999.
  • Step 2: Determine the total number of decimal places in the factors.
    0.1\quad 0.1 has 1 decimal place.
    0.999\quad 0.999 has 3 decimal places.
    Therefore, the product should have 1+3=41 + 3 = 4 decimal places.
  • Step 3: Position the decimal in the product calculated in step 1.
    999\quad 999 with 4 decimal places becomes 0.09990.0999.

Therefore, the product of 0.1×0.999 0.1 \times 0.999 is 0.0999 0.0999 .

Answer

0.0999 0.0999

Exercise #5

0.01×0.101= 0.01\times0.101=

Video Solution

Step-by-Step Solution

To solve the multiplication of 0.01×0.1010.01 \times 0.101, follow these steps:

  • Step 1: Consider both numbers without decimals as whole numbers. Here, interpret 0.010.01 as 11 and 0.1010.101 as 101101.
  • Step 2: Multiply these whole numbers: 1×101=1011 \times 101 = 101.
  • Step 3: Count the number of decimal places in each factor. For 0.010.01, there are 2 decimal places. For 0.1010.101, there are 3 decimal places, totaling 2+3=52 + 3 = 5 decimal places in the product.
  • Step 4: Insert a decimal point in the integer product of 101101 to give it 5 decimal places. Starting from the right of the number, move the decimal point 5 places to the left, yielding 0.001010.00101.

Thus, the correct answer is 0.00101\mathbf{0.00101}, which corresponds to choice 3\mathbf{3}.

Answer

0.00101 0.00101

Exercise #6

0.01×0.300= 0.01\times0.300=

Video Solution

Step-by-Step Solution

To solve this problem, we'll use the following steps:

  • Step 1: Multiply the numbers as if they were whole numbers.
  • Step 2: Count the number of decimal places in the original numbers.
  • Step 3: Position the decimal point in the product accordingly.

Let's go through each step in detail:
Step 1: Multiply 1×300=300 1 \times 300 = 300 .
Step 2: Count the decimal places: 0.01 0.01 has 2 decimal places and 0.300 0.300 has 3 decimal places, making a total of 5 decimal places.
Step 3: Place the decimal point in the result 300, counting 5 places from the right: 0.00300 0.00300 (we can drop the trailing zeros to write it as 0.003 0.003 ).

Therefore, the solution to the problem is 0.003 0.003 .

Answer

0.003 0.003

Exercise #7

0.01×0.315= 0.01\times0.315=

Video Solution

Step-by-Step Solution

To solve the problem 0.01×0.315 0.01 \times 0.315 , we'll follow these steps:

  • Step 1: Multiply the numbers ignoring the decimal points.
  • Step 2: Place the decimal point in the product according to the combined decimal places in the original numbers.

Let's proceed through each step:

First, multiply the numbers as whole numbers: 1×315=315 1 \times 315 = 315 .

Next, count the total number of decimal places in the factors. The number 0.01 0.01 has two decimal places, and 0.315 0.315 has three decimal places, adding up to five decimal places.

Therefore, in the product, we need to place the decimal point five places from the right.

Starting from 315 315 , we place the decimal point to get 0.00315 0.00315 . Since we add three leading zeros to accommodate the five decimal places total.

Thus, the result of 0.01×0.315 0.01 \times 0.315 is 0.00315 0.00315 .

Answer

0.00315 0.00315

Exercise #8

0.01×0.50= 0.01\times0.50=

Video Solution

Step-by-Step Solution

To solve this problem, follow these steps:

  • Step 1: Multiply the numbers without considering the decimals. Calculate 1×50=501 \times 50 = 50.
  • Step 2: Count the total number of decimal places in both original numbers. 0.010.01 has two decimal places, and 0.500.50 has two decimal places. This gives a total of four decimal places.
  • Step 3: Apply the total number of decimal places to the whole number product from Step 1. Therefore, 5050 becomes 0.0050.005.

Thus, the calculation shows that 0.01×0.50=0.0050.01 \times 0.50 = 0.005.

Therefore, the solution to the problem is 0.005\textbf{0.005}.

Answer

0.005 0.005

Exercise #9

0.01×0.45= \text{0}.01\times0.45=

Video Solution

Step-by-Step Solution

To solve this multiplication problem, we will follow these steps:

  • Step 1: Convert both decimal numbers to fractions or remove the decimals by considering them as whole numbers.
  • Step 2: Multiply these whole numbers.
  • Step 3: Place the decimal in the resulting product correctly by counting the sum of the decimal places in the original numbers.

Now, let's work through each step:

Step 1: We have the numbers 0.010.01 and 0.450.45.
Convert 0.010.01 to 1100\frac{1}{100} and 0.450.45 to 45100\frac{45}{100}.

Step 2: Multiply 1100×45100=1×45100×100=4510000\frac{1}{100} \times \frac{45}{100} = \frac{1 \times 45}{100 \times 100} = \frac{45}{10000}.

Step 3: Convert 4510000\frac{45}{10000} back to a decimal form. Since 1000010000 has 4 zeros, move the decimal four places to the left: 0.00450.0045.

Therefore, the product of 0.010.01 and 0.450.45 is 0.00450.0045.

Answer

0.0045 0.0045

Exercise #10

0.01×285.11= 0.01\times285.11=

Video Solution

Step-by-Step Solution

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

  • Step 1: Multiply 0.01 0.01 by 285.11 285.11 considering decimal multiplication rules.
  • Step 2: Determine the placement of the decimal point in the product.
  • Step 3: Identify the correct answer choice based on the calculation.

Now, let's work through each step:

Step 1: First, convert the numbers into whole numbers and multiply:

0.01=1100 0.01 = \frac{1}{100} and 285.11=28511/100 285.11 = 28511/100 .

Ignoring the decimals temporarily, calculate 1×28511=28511 1 \times 28511 = 28511 .

Step 2: Determine the placement of the decimal point:

Since 0.01 0.01 has 2 decimal places and 285.11 285.11 has 2 decimal places, the total number of decimal places in the product is 2+2=4 2 + 2 = 4 .

Adjust the product 28511 28511 by placing the decimal point 4 places from the end:

This gives us 2.8511 2.8511 .

Step 3: Compare this result with the given choices.

The correct answer is the choice that matches our calculation:

The solution to the problem is 2.8511 2.8511 .

Answer

2.8511 2.8511

Exercise #11

0.01×3.5= 0.01\times3.5=

Video Solution

Step-by-Step Solution

The task is to find the product of two decimal numbers: 0.01 0.01 and 3.5 3.5 . Follow these steps to compute the product:

  • Step 1: Remove the decimal points and multiply as if they are whole numbers. Multiplying 1 1 by 35 35 gives 35 35 .
  • Step 2: Count the total number of decimal places in both decimal numbers. The number 0.01 0.01 has 2 decimal places, and 3.5 3.5 has 1 decimal place, for a total of 3 decimal places.
  • Step 3: Place the decimal point in the product so that the result has the same total number of decimal places counted in step 2. Thus, 35 35 becomes 0.035 0.035 .

Following these steps ensures the decimal point is positioned correctly, resulting in the product 0.035 0.035 .

Therefore, the solution to the problem is 0.035 0.035 .

Answer

0.035 0.035

Exercise #12

0.01×44.9= 0.01\times44.9=

Video Solution

Step-by-Step Solution

To solve the problem of multiplying 0.010.01 by 44.944.9, we follow these steps:

  • Step 1: Convert numbers to eliminate decimals. Multiply 11 by 449449 (as 0.01=11000.01 = \frac{1}{100} and 44.9=4491044.9 = \frac{449}{10}).

  • Step 2: Perform the multiplication 1×4491 \times 449, which equals 449449.

  • Step 3: Adjust for decimal places. Since there are three decimal places combined in 0.010.01 and 44.944.9 (two from 0.010.01 and one from 44.944.9), the result 449449 should have three decimal places.

The correct placement of the decimal point gives us 0.4490.449.

Therefore, the solution to the problem is 0.449\mathbf{0.449}.

Answer

0.449 0.449

Exercise #13

0.01×4.8= 0.01\times4.8=

Video Solution

Step-by-Step Solution

To solve this problem, we'll multiply the decimal numbers 0.01 0.01 and 4.8 4.8 .

Here's how we can approach this:

  • Step 1: Identify the number of decimal places.
    - 0.01 0.01 has two decimal places.
    - 4.8 4.8 has one decimal place.
    - Total decimal places in the product will be 2+1=3 2 + 1 = 3 .
  • Step 2: Multiply the numbers as whole numbers, ignoring the decimal point.
    Multiply 1 1 (from 0.01 0.01 ) by 48 48 (from 4.8 4.8 ): 1×48=48 1 \times 48 = 48 .
  • Step 3: Place the decimal point in the product.
    Given that there are three decimal places in total, the product 48 48 becomes 0.048 0.048 .

Therefore, the solution to the problem is 0.048 0.048 .

Answer

0.048 0.048

Exercise #14

0.01×55.31= 0.01\times55.31=

Video Solution

Step-by-Step Solution

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

  • Step 1: Multiply the numbers as if they were whole numbers.
  • Step 2: Count the total number of decimal places in both the numbers and place the decimal point in the product accordingly.

Now, let's work through each step:
Step 1: Multiply 55.3155.31 by 11, which gives 55.3155.31.
Step 2: Since 0.010.01 has 2 decimal places, moving the decimal place in 55.3155.31 two places to the left gives us 0.55310.5531.

Therefore, the solution to the problem is 0.5531 0.5531 , which corresponds to choice 33.

Answer

0.5531 0.5531

Exercise #15

0.1×2.4= 0.1\times2.4=

Video Solution

Step-by-Step Solution

To solve this problem, follow these steps:

  • Step 1: Temporarily ignore the decimals and multiply 11 by 2424. The product is 2424.
  • Step 2: Count the decimal places in both numbers. 0.10.1 has one decimal place, and 2.42.4 has one decimal place. This gives a total of two decimal places.
  • Step 3: Place the decimal point in the product, which is 2424, to account for the two decimal places. Thus, 2424 becomes 0.240.24.

Therefore, the solution to the problem 0.1×2.40.1 \times 2.4 is 0.240.24.

Answer

0.24 0.24

Exercise #16

0.1×33.4= 0.1\times33.4=

Video Solution

Step-by-Step Solution

To solve the problem of finding 0.1×33.40.1 \times 33.4, we'll employ the following method:

  • Step 1: Multiply the numbers without considering decimals.
    Calculate 1×33.4=33.41 \times 33.4 = 33.4.
  • Step 2: Determine the decimal placement.
    The number 0.10.1 has one decimal place, and 33.433.4 has one decimal place. Therefore, the product should have 1+1=21 + 1 = 2 decimal places.
  • Step 3: Apply the decimal adjustment.
    Take the product 33.433.4 and insert two decimal places from the right. This results in 3.343.34.

Thus, the solution to the problem 0.1×33.40.1 \times 33.4 is 3.34\mathbf{3.34}.

Answer

3.34 3.34

Exercise #17

0.1×3.5= 0.1\times3.5=

Video Solution

Step-by-Step Solution

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

  • Step 1: Multiply the numbers without considering the decimal point.
  • Step 2: Count the total number of decimal places in the numbers being multiplied.
  • Step 3: Position the decimal point in the product accordingly.

Now, let's work through each step:

Step 1: Multiply 0.1 0.1 by 3.5 3.5 as whole numbers 1×35=35 1 \times 35 = 35 .

Step 2: Count the decimal places: 0.1 0.1 has 1 decimal place, and 3.5 3.5 has 1 decimal place, totaling 2 decimal places.

Step 3: In the product 35 35 , place the decimal point such that there are 2 decimal places: This gives us 0.35 0.35 .

Therefore, the solution to the problem is 0.35 0.35 .

Answer

0.35 0.35

Exercise #18

0.1×7.33= 0.1\times7.33=

Video Solution

Step-by-Step Solution

Let's solve the problem of multiplying 0.10.1 and 7.337.33 step by step.

Step 1: Rewrite the two numbers without considering the decimal points. Calculate the product of 10 and 733.

Step 2: The result of 10×73310 \times 733 is 73307330.

Step 3: Count the total number of decimal places in the original factors 0.10.1 and 7.337.33.
- 0.10.1 has 1 decimal place.
- 7.337.33 has 2 decimal places.
Together, they amount to 3 decimal places.

Step 4: In the product 73307330, move the decimal point backwards to account for the 3 decimal places. So, the decimal point goes three places from the end of the number.

The result is 0.7330.733.

Therefore, 0.1×7.33=0.7330.1 \times 7.33 = 0.733.

The correct answer choice is 0.7330.733.

Answer

0.733 0.733

Exercise #19

0.1×74.8= 0.1\times74.8=

Video Solution

Step-by-Step Solution

To solve this problem, let's follow these steps:

  • Identify and Analyze Decimal Places: Both numbers 0.1 0.1 and 74.8 74.8 have decimal points. Specifically, 0.1 0.1 has one decimal place, and 74.8 74.8 has one decimal place, making a total of two decimal places.
  • Perform Multiplication: Multiply the numbers as if they were whole numbers. Ignoring decimal points, multiply 1×748 1 \times 748 , which equals 748 748 .
  • Place the Decimal Point: Since the multiplication involves two decimal places in total (one from each factor), the product 748 748 should be adjusted to have two decimal places. Thus, it becomes 7.48 7.48 .

Thus, the result of multiplying 0.1×74.8 0.1 \times 74.8 is 7.48\mathbf{7.48}.

The correct answer is choice 2: 7.48\mathbf{7.48}.

Answer

7.48 7.48