PSLE Natalie baked a total of 27 large and small cakes in the ratio of 7 : 2. She decorated each cake with some cranberries in the ratio of 3 : 2. She used a total of 264 cranberries to decorate all the small cakes and 7 large cakes.
- How many small cakes did Natalie bake?
- What was the number of cranberries used to decorate all the small cakes?
- How many more cranberries did Natalie need to decorate the remaining large cakes?
(a)
Fraction of the cakes that were large ones =
77 + 2 =
79Number of large cakes
=
79 x 27
= 21
Number of small cakes
= 27 - 21
= 6
|
Large cakes |
Small cakes |
Total |
Number |
7 |
6 |
|
Value |
3 u |
2 u |
|
Total value |
21 u |
12 u |
33 u |
(b)
Number of cranberries used to decorate 7 large cakes and 6 small cakes
= 21 u + 12 u
= 33 u
33 u = 264
1 u = 264 ÷ 33 = 8
Number of cranberries used to decorate all the small cakes
= 12 u
= 12 x 8
= 96
(c)
Number of cranberries to decorate one large cake
= 3 u
= 3 x 8
= 24
Number of remaining large cakes that were decorated yet
= 21 - 7
= 14
Number of more cranberries that Natalie needed to decorate the remaining large cakes
= 14 x 24
= 336
Answer(s): (a) 6; (b) 96; (c) 336