Ratio P6 2010 SA2 Nanyang P1 Q21

The cost of 3 mangoes is the same as the cost of 5 grapefruits. The cost of 3 mangoes is also the same as the cost of 10 pears. Find the ratio of the cost of a mango to the cost of a grapefruit to the cost of a pear.
(Ans : 10 : 6 : 3)

3 M --> 5 G

M/G --> 5/3 = 10/6


3 M --> 10 P

M/P --> 10/3

M : G : P = 10 : 6 : 3


Alternative method
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Assume 3 mangoes = 5 grapefruits = 10 pears = $1
1 M --> 1/3

1 G --> 1/5

1 P --> 1/10

M : G : P = 1/3 : 1/5 : 1/10
               = 10 : 6 : 3    Multiply by 30