Decimals

Question 1

How do you multiply decimals?

Answer 1

1. Ignore the decimals and perform the multiplication as per normal using a multiplication algorithm.
2. Once the numbers are multiplied, put the decimal place back in according to how many numbers are behind the decimal place in the question.

Question 2

What is the process you would use to add or subtract decimals?

Answer 2

1. Align the decimal points in the question underneath each other
2. Add any additional zeros in the gaps of the algorithm
3. Use an addition algorithm as per usual
4. Put the decimal place in the answer directly below those in the question

Question 3

How do you divide decimals by whole numbers?

Answer 3

1. Complete the division as per usual using a division algorithm
2. Keep the decimal place in the answer directly above the decimal place in the algorithm

Question 4

How do you divide decimals by other decimals?

Answer 4

1. Change the number in the divisor into a whole number by moving the decimal place to the right
2. Whatever change is made to the divisor, he dividend
3. Use a division algorithm as per usual with the two new numbers

Question 5

What process should be used when dividing by multiples of 10? E.g. Divide 9284 by 700.

Answer 5

1. Ignore the number at the front of the divisor and move your decimal place according to how many zeros are in the divisor
2. Divide by the number at the front of the divisor using a division algorithm

Question 6

How do you convert decimals to fractions?

Answer 6

1. Remove the decimal place to write the decimal as a whole number
2. Put the number over 10, 100, 1000 etc. depending on how many numbers are after the decimal place
3. Simplify the fraction if possible!

Question 7

How do you convert fractions to decimals?

Answer 7

Divide the numerator by the denominator. Remember, the denominator goes on the outside of the algorithm and the numerator goes on the inside.

Question 8

How do you convert percentages to fractions?

Answer 8

Divide by 100 i.e. Move th decimal place two spaces to the left.

Question 9

How do you convert a decimal to a percentage?

Answer 9

Multiply by 100 i.e. move the decimal places two spaces to the right

Question 10

What process do you use to round decimals?

Answer 10

1. Cut the number after the required decimal place.
2. Circle the critical digit.
3. Round the rounding digit up if the critical digit is 5 or greater OR round down if the critical digit is less than 5 (0, 1, 2, 3, 4).

Question 11

How do you multiply by powers of ten?

Answer 11

Move the decimal place to the right according to how many zeros there are in the multiplier.

Question 12

How do you divide by powers of ten?

Answer 12

Move the decimal point to the left according to how many zeros there are in the divisor.