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A farmer spent $35 on feed for chickens and goats. He spent 40% money on chicken feed, which he bought at a 20% discount off the full price, and spent the rest on goat feed, which he bought at full price. If the farmer had paid full price for both the chicken feed and the goat feed, what amount would he have spent on the chicken feed and goat feed combined?
A. $37.80
B. $38.50
C. $39.20
D. $39.50
E. $40.60

A farmer spent 40% money on chicken feed, so he spent 0.4*$35=$14 on chicken feed, thus he spent the remaining 35-14=$21 on goat feed.

Now, since he bought chicken feed at a 20% discount then the original price of it was x*0.8=$14 --> x=$17.5.

Therefore if the farmer had paid full price for both the chicken feed and the goat feed, then he would he have spent 17.5+21=$38.5.

Answer: B.

Hope it's clear.
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You can write one equation right away I just broke down the solution into several steps to make it easier. If interested here it is: 0.4*35/0.8+0.6*35=38.5. Notice that you should divide 0.4*35 by 0.8 to get original price and not multiply.
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guys here is an easier way:
Let the farmer had 100 to spend.
He spent 40 on chickens and 60 on goats.
now actual price of chicken feed without discount
x-20%x=40
0.8x=40 or x=50
So without discount he would have spent 50+60=110
Now 110 for 100
For 35 it is 110/100*35=38.5

Posted from my mobile device

We know 60% of $35 was spent on goats, leaving us with $14 spent on chickens.

$14 spent was with discount --> $14 = x-0.20x --> 14 = 0.80x --> x = $17.5 (original price)

$17.5+$21 = $38.5

Hi All,

This question is essentially about arithmetic and taking the proper notes. You can go about the math steps in a couple of different ways though - depending on how you 'see' this information.

From the prompt, we know that the farmer spent $35 on feed.... 40% of his money on chicken feed.... and the rest on goat feed. This means that for every dollar he spent, $0.40 was spent on chicken feed and $0.60 was spent on goat feed. With a total of $35 spent, we can easily break down the two totals....

(.4)($35) = $14.00 on chicken feed
The rest = $35 - $14 = $21 on goat feed

We were also told that the chicken feed was purchased at a 20% discount, which means that the farmer paid 80% of the regular price for that feed.

$14.00 = (.8)(Regular Price)
$14/.8 = (Regular Price)
$140/8 = (Regular Price)
$17.50 = (Regular Price)

We're asked what the price would have been if the farmer had bought both feeds at full price.... $21 + $17.50 = $38.50

Final Answer:

GMAT assassins aren't born, they're made,
Rich
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