PSLE
Mr Ee used ³₁₀ of his money to buy 6 starfruits and 8 persimmons. The cost of 3 starfruits was the same as that of 4 persimmons. What was the most number of persimmons that Mr Ee could buy with the money he had left?
Fraction of his money that he had left
= 1 - ³₁₀ 
= ⁷₁₀

Let the cost of 1 starfruit be 1 S.
Let the cost of 1 persimmon be 1 P.

3 S = 4 P _(x2)
6 S = 8 P

Since Mr Ee wants to buy persimmons with the money he had left, 6 starfruits will be substituted as 8 persimmons.

³₁₀ of his money
= 6 S + 8 P
= 8 P + 8 P
= 16 P

³₁₀ of his money → 16 P
¹₁₀ of his money → ¹⁶₃ P
⁷₁₀ of his money → 7 x ¹⁶₃ P = 37¹₃ P

Maximum number of persimmons he could buy with the money that he had left = 37

Answer(s): 37