Page 148 - NUMINO TG_2A
P. 148
Activity 2 Missing Numbers 09Math Balance Unit
jOb ective Find missing numbers in subtraction sentences.
Activity 2 Missing Numbers 1. Textbook Instructions
1 Use the figures to find the missing numbers. Have students find missing numbers using
various methods and complete subtraction
18 - 11 = 7 sentences to make the total number on both
sides of the equal sign the same.
So, the missing number is 11 .
a 15 - 12 = 3 1. Use the elimination method as shown in
the diagram to find the missing number in
b 21 - 14 = 7 18 7.
c 18 - 13 = 5 Group 7 objects.
Cross out the remaining objects.
The number of crossed out objects is the
missing number.
1b. Have students understand that the
subtraction requires regrouping.
Sentence 21 7
9. Math Balance 81
2. Build Understanding
Write the correct number in the . 2.
1.
14 8
24 8 8, 14 8 6
24 8 16 2. 14
Solution: 1. 24 8,
Answer: 1. 16 2. 6
2A Unit 09 131
jOb ective Find missing numbers in subtraction sentences.
Activity 2 Missing Numbers 1. Textbook Instructions
1 Use the figures to find the missing numbers. Have students find missing numbers using
various methods and complete subtraction
18 - 11 = 7 sentences to make the total number on both
sides of the equal sign the same.
So, the missing number is 11 .
a 15 - 12 = 3 1. Use the elimination method as shown in
the diagram to find the missing number in
b 21 - 14 = 7 18 7.
c 18 - 13 = 5 Group 7 objects.
Cross out the remaining objects.
The number of crossed out objects is the
missing number.
1b. Have students understand that the
subtraction requires regrouping.
Sentence 21 7
9. Math Balance 81
2. Build Understanding
Write the correct number in the . 2.
1.
14 8
24 8 8, 14 8 6
24 8 16 2. 14
Solution: 1. 24 8,
Answer: 1. 16 2. 6
2A Unit 09 131
