Solving word problems
A word problem tells a little story. We use 4 steps to solve it. This chapter is about whole numbers up to 1000, so we add or take away numbers.
Key idea
1 Understand the story. 2 Plan (add or take away?). 3 Solve it. 4 Check your answer.
Which words help?
Words like altogether, in all, more often mean add (+). Words like left, gives away, fewer often mean take away (−). These helper words are clues, but always think about the story too, not just the words. It also helps to draw a simple picture or write the numbers down before you begin.
Worked example
Ali has 120 marbles. He buys 30 more. How many now?
Step 1: he starts with 120. Step 2: "more" means add. Step 3: 120 + 30 = 150 marbles. Step 4 check: 150 − 30 = 120. Correct!
Remember
- Read slowly and picture the story.
- Choose add or take away.
- Always check your answer.