From the amounts that are given, the ratio of the earnings will be 3:2:1.
From the information, the eldest earns R270, the middle child earns R180 and the youngest earns R90.
Therefore, the common factor to the numbers will be 90. Therefore, the ratio will be:
270/90 = 3
180/90 = 2
90/90 = 1
The ratio is 3:2:1.
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