Which sign (+ or -) makes the number sentence true? - up to 100 in word problems: Example question
30 October 2026
Children often see number sentences with a missing sign and need to decide if it should be plus or minus. In word problems, understanding the story helps them choose the right operation.
Example question
Eli has 72 stickers. He gives 18 stickers to his friend. Which sign (+ or -) makes this number sentence true?
72? 18 = 54
Step 1
Look at the number sentence: 72? 18 = 54. We need to find the sign that makes this true.
Step 2
Think about the story. Eli gives stickers away, so he has fewer stickers now. This means we subtract.
Step 3
Try the minus sign: 72 - 18 = 54. Is this true? Yes, 72 minus 18 equals 54.
Answer The correct sign is minus (-). 72 - 18 = 54
After working through this example, your child will be able to spot when to use addition or subtraction in similar questions. They can now practise more word problems just like this one.
