ADDING AND SUBTRACTING DECIMALS (2) GRADE 3

Hello, How are you doing? Today, we are going to start a new lesson on Decimals.

Using Models to subtract Use one color for the greater number. Take away the number to be subtracted. The left number is the difference.

Steps for Subtraction Start with the hundredths. subtract the tenths. Subtract each place. Regroup if needed. Place the decimal point between the tenths and the ones in the difference.

Subtract 0.5 from 0.9 using Model = 0.4

Subtract 1.4 from

Is Subtracting Decimals like subtracting Whole numbers? Subtracting Decimals is like subtracting Whole numbers. Start with the digits farthest to the right, then subtract. Regroup if necessary.

Subtract 0.65 – 0.26 Answer – 0.39

Subtract 0.5 – 0.3 Answer- 0.2

An Adult’s toothbrush is 12.9 cm long while a child’s toothbrush is 9.8 cm long. How much longer is an adult’s toothbrush? Answer – 3.1 cm

Line up the decimal number, – 0.29 for subtraction Answer – 12.07

A bag containing Oranges and Grapes weigh 14.9 pounds. If oranges weigh 9.9 pounds, what is the weight of grapes? Answer – 5.0 pounds

Subtract 8.11 – 2.95 Answer – 5.16

Subtract 0.96 – 0.87 using model. Answer – 0.09

Which is greater? a) 0.69 – 0.25 b) 0.69 – 0.22 c) 0.69 – 0.24 d) 0.69 – 0.23

What should be taken away from 1.59 to get 0.87? Answer – 0.72

Which is not correct? a) 16.9 – 8.9 = 8.0 b) 16.9 – 8.9 = 7.9 c) 16.9 – 8.9 =8 d) 16.9 – 8.9 = 8.00

ASSESSMENT

1.What is the difference for 5.23 – 3.55? Answer- 1.68

2.The milometer of the Paul’s car shows 62.3 Km. How much farther does he have to ride to reach 62.5 Km? Answer- 0.2 km

3.Which is true? a) 3.4 – 2.1 = 1.5 b) 3.4 – 2.1 = 1.3 c) 3.4 – 2.1 = 0.3 d) 3.4 – 2.1 = 13.1

4.Alee had $ He spend $4.65 on a T-shirt. How much money was left with him? Answer - $6.95

5.Subtract 0.24 – 0.06 using model. Answer- 0.18

6.In a box of cookies, 0.65 of the cookies are chocolates. What decimal amount represents all the other cookies except chocolate? Answer- 0.35

7.Mr. John takes the train to the museum. Train ticket costs $ He paid the cashier $15 bill. How much money he get back? Answer- $0.25

8.The winning team got a score of 30.5 points. The team that came second got a score of 25.9 points. By how many points did the winning team win? Answer- 4.6 points

9.Subtract 1.5 – 0.99 Answer- 0.51

10.What should be added to 3.9 to get 5? Answer – 1.1

Recap Models to subtract Subtraction Rules Subtracting Decimals like subtracting Whole numbers. Solved Examples Practice Problems

Well Done! Now practice worksheets on the Lesson.