Xuan, Sarah and Nick baked some cookies. Xuan and Sarah baked
23 of the cookies. Sarah and Nick baked
37 of the cookies. Xuan and Nick baked 494 cookies altogether.
- What fraction of the cookies did Xuan and Nick bake altogether?
- How many cookies did the three girls bake in total?
| Xuan |
Sarah |
Nick |
Total |
| 2x7 |
1x7 |
3x7 |
| 4x3 |
3x3 |
7x3 |
| 12 u |
2 u |
7 u |
21 u |
(a)
The total number of cookies the same. Make the total number of cookies unchanged. LCM of 3 and 7 is 21.
Number of cookies baked by Sarah
= 9 u - 7 u
= 2 u
Number of cookies baked by Xuan and Nick
= 12 u + 7 u
= 19 u
Total number of tarts = 21 u
Fraction of the cookies baked by Xuan and Nick =
1921(b)
Total number of cookies baked by Xuan and Nick = 19 u
19 u = 494
1 u = 494 ÷ 19 = 26
Total number of cookies baked
= 21 u
= 21 x 26
= 546
Answer(s): (a)
1921; (b) 546
