PSLE
Lina baked a total of 30 large and small cakes in the ratio of 7 : 3. She decorated each cake with some cherries in the ratio of 8 : 3. She used a total of 354 cherries to decorate all the small cakes and 4 large cakes.

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

(a)
Number of large cakes
= ⁷₁₀ x 30
= 21

Number of small cakes
= 30 - 21
= 9

	Large cakes	Small cakes	Total
Number	4	9
Value	8 u	3 u
Total value	32 u	27 u	59 u

(b)
Number of cherries used to decorate 4 large cakes and 9 small cakes
= 32 u + 27 u
= 59 u

59 u = 354

1 u = 354 ÷ 59 = 6

Number of cherries used to decorate all the small cakes
= 27 u
= 27 x 6
= 162

(c)
Number of cherries to decorate one large cake
= 8 u
= 8 x 6
= 48

Number of remaining large cakes that were decorated yet
= 21 - 4
= 17

Number of more cherries that Lina needed to decorate the remaining large cakes
= 17 x 48
= 816

Answer(s): (a) 9; (b) 162; (c) 816