Review Adding, Subtracting, Multiplying and Dividing Decimals

To divide decimals we must move the decimal on the outside and the inside of the division symbol.

• Always

• Sometimes

• Never

When ​ (a)   decimals, I must always ​ (b)   the decimals.

• adding or subtracting

• line up

• multiplying or dividing

• get rid of

When ​ (a)   by a decimal, I must change the ​ (b)   (second or outside number) to a ​ (c)   .  Then I move the decimal the that same amount in the ​ (d)   (first or inside number).  Then ​ (e)   like normal.

• dividing

• whole number

• dividend

• divisor

• divide

• multiplying

• multiply

• fraction

What is the value of the expression 0.5 + 0.74?

9.3 × 6.2 + 2.3 - 6.2 ÷ 1.1=

• 55

• 54

• 55.3236363636

• 54.3236363636

0.21 - 3.26 + 69.3 × 3.33 ÷ .12=

• 1910.25

• 1910.025

• 1920.025

• 1920.25

9.5 × 63.1 - 3.22 + 3.2 ÷ .1=

• 628.23

• 630

• 625

• 629.23

-12.4 + 9.2 + 1 

Mathematical Equivalence

ON

14 - (12.1 - 3.2²)

• 4.64

• 12.14

• 19.759

• 16.64

Which operation would you use to solve the problem?

Alessandro had to wait 2.73 minutes for the bus in the morning and 4.19 minutes for the bus in the afternoon. How many minutes did he wait altogether?

• Adding decimals

• Subtracting decimals

• Multiplying decimals

• Dividing decimals