rahul.s wrote:A certain fruit stand sold apples for $0.70 each and bananas for $0.50 each. If a customer purchased both apples and bananas from the stand for a total of $6.30, what total number of apples and bananas did the customer purchase?
(A) 10
(B) 11
(C) 12
(D) 13
(E) 14
OA: B
Well, the number of apples and bananas bought got to be positive integers only. One may wonder of how to solve (answer uniquely) a single linear equation in two variables here, but the first statement that I have made is nearly equivalent to a second dissimilar equation/information in the same two variables, and the question may now be answered uniquely. See, how we could go about it.
If the customer purchases, a apples and b bananas, then
$0.70 a + $0.50 b = $6.30 such that b = (63 - 7 a)/5. There must be a unique pair of positive integers for a and b, if this question really holds. For 7 a, a number < 63, ending with a '3' or an '8' could give us b, a positive integer. We've 7*4 = 28 and 7*9 = 63 to work on, but, since the customer purchased both apples and bananas, therefore both a and b are positive integers. Can't take 63 for 7 a. Take 7 a = 28 and hence a = 4 and b = 7 to answer the total number of apples and bananas that the customer has purchased as a + b = 4 + 7 = [spoiler]
11[/spoiler].
[spoiler]
B[/spoiler]
