srikanth9502 wrote:
The average American spends y dollars on food per month, except during January, when food purchases are x percent lower than they are in other months. Which of the following reepresents food purchases, in dollars, for the first 9 months of a year?
A)9y – xy/100
B)9y + xy
C)9y – xy
D)(9y-xy)/9
E)y-xy/6
Assign values.
Let y dollars per month be 10
Let x percent less for January be 10
Eight month total is (8 * 10) = $80
January total is (.90)(10) = $9
Total for nine months = $89
With y = 10 and x = 10, find the answer choice that yields $89.
Answers B, C, D, and E can be eliminated quickly.
Answer B is 9y + xy. 9y = (9*10) = 90 is too high already. Adding anything will make it higher.
Answer C, 9y – xy. Easy and quick calculation shows result is negative.
(9*10) + (10*10) =
(90) - (100) = -10
If C is negative, then Answer D, (9y-xy)/9, is too. Its numerator is identical to answer C.
If C is negative with (
9y - xy), then Answer E's numerator,
1y - xy, will be more negative.
Answer A, which initially looked strange because I read the denominator incorrectly, remains: 9y – xy/100
(9 * 10) - \(\frac{(10*10)}{100}\) =
90 - 1 = 89
Answer A
_________________
SC Butler has resumed!Get
two SC questions to practice, whose links you can find by date,
here.Tell me, what is it you plan to do with your one wild and precious life? --
Mary Oliver