Online Test — Subtraction Strategies
10 Questions • 15 min • Chapter MCQ
15:00
Question 1 of 10
Use counting backward to find 9 - 5.
3
4
5
6
Explanation: Start at 9, count back 5: 8,7,6,5,4
Question 2 of 10
Which addition fact helps solve 12 - 7?
7+5=12
7+6=13
7+4=11
7+7=14
Explanation: 7 + 5 = 12, so 12 - 7 = 5
Question 3 of 10
Solve mentally: 15 - 8
6
7
8
9
Explanation: Related fact: 8+7=15, so 15-8=7
Question 4 of 10
Riya has 20 stickers. She gives 6 stickers to her friend. How many stickers are left?
12
13
14
15
Explanation: 20 - 6 = 14 (count back: 19,18,17,16,15,14)
Question 5 of 10
Find the missing number: ? - 3 = 9
6
9
12
15
Explanation: 3 + 9 = 12, so 12 - 3 = 9
Question 6 of 10
Which fact family includes 7, 9, and 16?
7+9=16, 16-7=9
7+8=15, 15-7=8
9+6=15, 15-9=6
7+10=17, 17-7=10
Explanation: 7+9=16 and 16-7=9 are correct related facts
Question 7 of 10
Use counting backward: 14 - 5
7
8
9
10
Explanation: Start at 14, count back: 13,12,11,10,9
Question 8 of 10
There are 17 eggs in a carton. Mom uses 8 eggs to make a cake. How many eggs are left?
7
8
9
10
Explanation: 17 - 8 = 9 (related fact: 8+9=17)
Question 9 of 10
Find the missing number: 16 - ? = 9
5
6
7
8
Explanation: 16 - 9 = 7, so 16 - 7 = 9
Question 10 of 10
What is the best mental strategy for 11 - 3?
Counting backward
Related facts
Break apart
Guess
Explanation: 3 is small, so counting backward works well: 11,10,9,8