Mrs Sih baked 9 cookies more than cakes. Each cookie needed 0.07 kg of flour while each strudel needed 0.5 kg of flour. She used 1.95 kg more flour for the cakes than for the cookies. How many cookies did Mrs Sih bake?
| |
Cakes |
Cookies |
Difference |
| Number |
1 u |
1 u + 9 |
|
| Value |
0.5 |
0.07 |
|
| Total value |
0.5 u |
0.07 u + 0.63 |
0.43 u - 0.63 |
Amount of flour needed for cookies
= 0.07 x (1 u + 9)
= 0.07 u + 0.63
Amount of more flour for the cakes than the cookies
= 0.5 u - (0.07 u + 0.63)
= 0.5 u - 0.07 u - 0.63
= 0.43 u - 0.63
0.43 u - 0.63 = 1.95
0.43 u = 1.95 + 0.63
0.43 u = 2.58
1 u = 2.58 ÷ 0.43 = 6
Number of cookies baked
= 1 u + 9
= 6 + 9
= 15
Answer(s): 15
