Mrs Ong baked 9 cookies more than strudels. Each cookie needed 0.06 kg of flour while each swiss roll needed 0.5 kg of flour. She used 1.22 kg more flour for the strudels than for the cookies. How many cookies did Mrs Ong bake?
| |
Strudels |
Cookies |
Difference |
| Number |
1 u |
1 u + 9 |
|
| Value |
0.5 |
0.06 |
|
| Total value |
0.5 u |
0.06 u + 0.54 |
0.44 u - 0.54 |
Amount of flour needed for cookies
= 0.06 x (1 u + 9)
= 0.06 u + 0.54
Amount of more flour for the strudels than the cookies
= 0.5 u - (0.06 u + 0.54)
= 0.5 u - 0.06 u - 0.54
= 0.44 u - 0.54
0.44 u - 0.54 = 1.22
0.44 u = 1.22 + 0.54
0.44 u = 1.76
1 u = 1.76 ÷ 0.44 = 4
Number of cookies baked
= 1 u + 9
= 4 + 9
= 13
Answer(s): 13
