Lets examine by plugging values in this case a=10 b=30 and c=30

Quantity A is (20+30)% of 30 or \(\frac{50}{100} \times 30\)

Quantity B is 30% of (20+30) or \(\frac{30}{100} \times 50\)

See in both cases the numerator and the denominator is always the same i.e \(30 \times 50\) and \(100\) respectively.

The answer is indeed C.

Explanation

It is always the case that, for two positive quantities, M% of N = N% of M. In this case, (a + b) makes the problem appear more complicated, but the principle still applies. Algebraically:

Quantity A : \(\frac{a+b}{100}\times c\)

Quantity B: \(\frac{c}{100}\times (a+b)\)


Both quantities can be simplified to \(\frac{(a+b) \times c}{100}\). The two quantities are equal.

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