Mrs Chau baked 402 more cookies than Mary. After Mrs Chau sold 162 of her cookies, she had 3 times as many cookies as Mary.
- How many cookies did Mary bake?
- How many cookies did Mrs Chau bake?
| |
Mary |
Mrs Chau |
| Before |
1 u |
1 u + 402 |
| Change |
|
- 162 |
| After |
1 u |
1 u + 240 |
(a)
After
Number of cookies that Mary had = 1 u
Number of cookies that Mrs Chau had = 3 x 1 u = 3 u
Before
Number of cookies that Mary baked = 1 u
Number of cookies that Mrs Chau baked = 1 u + 402
3 u = 1 u + 402 - 162
3 u - 1 u = 240
2 u = 240
1 u = 240 ÷ 2 = 120
Number of cookies that Mary baked
= 1 u
= 120
(b)
Number of cookies that Mrs Chau baked
= 1 u + 402
= 120 + 402
= 522
Answer(s): (a) 120; (b) 522
