PSLE
Eva baked a total of 48 large and small cakes in the ratio of 5 : 3. She decorated each cake with some grapes in the ratio of 3 : 2. She used a total of 216 grapes to decorate all the small cakes and 12 large cakes.

1. How many small cakes did Eva bake?
2. What was the number of grapes used to decorate all the small cakes?
3. How many more grapes did Eva need to decorate the remaining large cakes?

(a)
Fraction of the cakes that were large ones = ⁵_{5 + 3} = ⁵₈

Number of large cakes
= ⁵₈ x 48
= 30

Number of small cakes
= 48 - 30
= 18

	Large cakes	Small cakes	Total
Number	12	18
Value	3 u	2 u
Total value	36 u	36 u	72 u

(b)
Number of grapes used to decorate 12 large cakes and 18 small cakes
= 36 u + 36 u
= 72 u

72 u = 216

1 u = 216 ÷ 72 = 3

Number of grapes used to decorate all the small cakes
= 36 u
= 36 x 3
= 108

(c)
Number of grapes to decorate one large cake
= 3 u
= 3 x 3
= 9

Number of remaining large cakes that were decorated yet
= 30 - 12
= 18

Number of more grapes that Eva needed to decorate the remaining large cakes
= 18 x 9
= 162

Answer(s): (a) 18; (b) 108; (c) 162