PSLE
Marion baked a total of 49 large and small cakes in the ratio of 4 : 3. She decorated each cake with some grapes in the ratio of 7 : 2. She used a total of 238 grapes to decorate all the small cakes and 11 large cakes.

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

(a)
Fraction of the cakes that were large ones = ⁴_{4 + 3} = ⁴₇

Number of large cakes
= ⁴₇ x 49
= 28

Number of small cakes
= 49 - 28
= 21

	Large cakes	Small cakes	Total
Number	11	21
Value	7 u	2 u
Total value	77 u	42 u	119 u

(b)
Number of grapes used to decorate 11 large cakes and 21 small cakes
= 77 u + 42 u
= 119 u

119 u = 238

1 u = 238 ÷ 119 = 2

Number of grapes used to decorate all the small cakes
= 42 u
= 42 x 2
= 84

(c)
Number of grapes to decorate one large cake
= 7 u
= 7 x 2
= 14

Number of remaining large cakes that were decorated yet
= 28 - 11
= 17

Number of more grapes that Marion needed to decorate the remaining large cakes
= 17 x 14
= 238

Answer(s): (a) 21; (b) 84; (c) 238