PSLE Jaslyn baked a total of 45 large and small cakes in the ratio of 7 : 2. She decorated each cake with some cherries in the ratio of 8 : 3. She used a total of 486 cherries to decorate all the small cakes and 3 large cakes.
- How many small cakes did Jaslyn bake?
- What was the number of cherries used to decorate all the small cakes?
- How many more cherries did Jaslyn need to decorate the remaining large cakes?
(a)
Fraction of the cakes that were large ones =
77 + 2 =
79Number of large cakes
=
79 x 45
= 35
Number of small cakes
= 45 - 35
= 10
|
Large cakes |
Small cakes |
Total |
Number |
3 |
10 |
|
Value |
8 u |
3 u |
|
Total value |
24 u |
30 u |
54 u |
(b)
Number of cherries used to decorate 3 large cakes and 10 small cakes
= 24 u + 30 u
= 54 u
54 u = 486
1 u = 486 ÷ 54 = 9
Number of cherries used to decorate all the small cakes
= 30 u
= 30 x 9
= 270
(c)
Number of cherries to decorate one large cake
= 8 u
= 8 x 9
= 72
Number of remaining large cakes that were decorated yet
= 35 - 3
= 32
Number of more cherries that Jaslyn needed to decorate the remaining large cakes
= 32 x 72
= 2304
Answer(s): (a) 10; (b) 270; (c) 2304