Answer: Choice A
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Explanation:
The equation shown for choice A is in the form p*(q*r) = (p*q)*r which is the general format for the associative property of multiplication.
In this case, p = 2.5, q = 1/5 and r = 2/3.
The order of p,q,r stays the same while the parenthesis shift around. The stuff in the parenthesis is done first before anything else. Though with multiplication, the order doesn't matter which is why we can freely shift the parenthesis like this.
Addition has a similar rule which says p+(q+r) = (p+q)+r.
