PSLE Joelle baked a total of 21 large and small cakes in the ratio of 5 : 2. She decorated each cake with some cranberries in the ratio of 5 : 3. She used a total of 228 cranberries to decorate all the small cakes and 4 large cakes.
- How many small cakes did Joelle bake?
- What was the number of cranberries used to decorate all the small cakes?
- How many more cranberries did Joelle need to decorate the remaining large cakes?
(a)
Fraction of the cakes that were large ones =
55 + 2 =
57Number of large cakes
=
57 x 21
= 15
Number of small cakes
= 21 - 15
= 6
|
Large cakes |
Small cakes |
Total |
Number |
4 |
6 |
|
Value |
5 u |
3 u |
|
Total value |
20 u |
18 u |
38 u |
(b)
Number of cranberries used to decorate 4 large cakes and 6 small cakes
= 20 u + 18 u
= 38 u
38 u = 228
1 u = 228 ÷ 38 = 6
Number of cranberries used to decorate all the small cakes
= 18 u
= 18 x 6
= 108
(c)
Number of cranberries to decorate one large cake
= 5 u
= 5 x 6
= 30
Number of remaining large cakes that were decorated yet
= 15 - 4
= 11
Number of more cranberries that Joelle needed to decorate the remaining large cakes
= 11 x 30
= 330
Answer(s): (a) 6; (b) 108; (c) 330