Addition Subtraction Problem Solving

Name:

Date:

Maths detective with calculator and magnifying glass

🔍 Part 1: Maths Detective - Estimation First!

1. Sarah has 347 stickers. Her friend gives her 186 more stickers. About how many stickers does Sarah have now?

First, estimate by rounding: 347 rounds to _______ and 186 rounds to _______

My estimate: _______ + _______ = _______

Exact answer: _______

2. At the school fair, 523 people came on Saturday and 287 people came on Sunday. How many more people came on Saturday than Sunday?

Estimate the difference: _______

Exact difference: _______

3. Tom saved $164 in January and $238 in February. About how much did he save altogether?

About $300

About $400

About $500

Show your working:

✓ Part 2: Check Your Answers!

4. Emma calculated 456 + 279 = 735. Check if her answer is correct using the inverse operation.

To check addition, I can use: _______ - _______ = _______

Is Emma's answer correct? _______

5. The school library had 642 books. They gave away 158 books to other schools. How many books are left?

My calculation:

Check using addition: _______ + 158 = _______

6. Compare these amounts and find the difference:

Jake's marbles: 425 | Lucy's marbles: 367

Who has more marbles? _______

How many more? _______

🌟 Part 3: Real-World Problem Solving

7. The Year 4 classes are collecting bottles for recycling. Room 12 collected 284 bottles, Room 13 collected 196 bottles, and Room 14 collected 315 bottles.

a) Estimate the total number of bottles: _______

b) Calculate the exact total:

c) How close was your estimate? _______

8. Challenge Problem: A shop had 750 items at the start of the day. They sold 268 items in the morning and 195 items in the afternoon. How many items are left?

Strategy I will use:

My working:

Answer: _______ items left

Check your answer: _______ + 268 + 195 = 750 ✓