Answer:
(c) Store A, $0.50 cheaper
Explanation:
When a price is discounted by a rate d, the multiplier of the price is (1 -d).
Store A
The discounted price is $50 × (1 -0.05) = $50×0.95 = $47.50
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Store B
The discounted price is $60 × (1 -0.20) = $60×0.80 = $48.00
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The price at Store A is less by ...
$48.00 -47.50 = $0.50