PSLE
Esther baked a total of 48 large and small cakes in the ratio of 7 : 5. She decorated each cake with some raspberries in the ratio of 7 : 3. She used a total of 348 raspberries to decorate all the small cakes and 8 large cakes.

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

(a)
Fraction of the cakes that were large ones = ⁷_{7 + 5} = ⁷₁₂

Number of large cakes
= ⁷₁₂ x 48
= 28

Number of small cakes
= 48 - 28
= 20

	Large cakes	Small cakes	Total
Number	8	20
Value	7 u	3 u
Total value	56 u	60 u	116 u

(b)
Number of raspberries used to decorate 8 large cakes and 20 small cakes
= 56 u + 60 u
= 116 u

116 u = 348

1 u = 348 ÷ 116 = 3

Number of raspberries used to decorate all the small cakes
= 60 u
= 60 x 3
= 180

(c)
Number of raspberries to decorate one large cake
= 7 u
= 7 x 3
= 21

Number of remaining large cakes that were decorated yet
= 28 - 8
= 20

Number of more raspberries that Esther needed to decorate the remaining large cakes
= 20 x 21
= 420

Answer(s): (a) 20; (b) 180; (c) 420