There are 240 animals in a farm. 40 goats are added and the fraction av goats is tripled. What is the new amount of goats?

40 + x = 3x

40 = 2x

x = 20 goats originally

60 goats now

There are 240 animals in a farm. 40 goats are added and the fraction av goats is tripled. What is the new amount of goats?

Let the fraction of goats at the start = x/240

Then.....3 times this = 3(x)/240

And when we add 40 to the original number we have that the new fractional amount = (x + 40) / (240 + 40)  =

(x + 40) / 280

So we have that

( x + 40)/ 280   =  (3x)  / 240      cross-multiply

240(x + 40) = 280 (3x)   simplify

240x + 9600  = 840x    subtract 240x from both sides

9600 = 600x     divide both sides by 600

16 = x    this is the number of goats at the beginning...and the fractional amount = 16 / 240  = 1/15

At the end....the number of goats = 16 + 40 = 56......and the fractional amount at the end  = 56/280  = 1/5

Verify that 3(1/15)  indeed = 3/15  = 1/5

CPhill: I think you may have read too much into this question!! I think EP's simple solution makes more sense!. Just another opinion.

The FRACTION of goats is tripled..not the NUMBER  (as I calculated earlier)

x/240 = original fraction

ADD 40 goats to TRIPLE the fraction

(x+40)/280 = 3(x/240)

x+40 = 840x/240

40 = 840x/240 - x

x=16  (original number)

x+40 =56   New number of goats

Well, of course you think EP’s simple solution makes more sense. Like usual, you are wrong. Your arteries have hardened from a diet of blarney.  You are a simpleminded, artless, baboon, who can only find unneeded complexity in simple interest rate problems.    

 EP corrected his answer. His arteries work well.  His diet has a low portion of blarney.

 Just another opinion –I didn’t read too much into it, I’m sure. 

GA

Thank you guys. In my book the correct answer is 60 goats after 40 new goats were aded.

More blarney from the unethical banker presented like the artless baboon he is.

 “In my book the correct answer is 60 goats after 40 new goats were added.”

Yeah, right!

So the reason the asker wrote 220 as his answer when he posted the question, is because, well, his school book was previously in the possession of a son of a banker, whose father accidentally cooked it along with the bank’s books. That was his downfall. It’s one thing to cook bankbooks, but damaging school property – it’s the “Big House” for you.