Exponents problems: 2^21 / [4^4 (4^4 + 4^5)]

[shooger]

Hi guys. I'm studying for the math section on the DAT, and this is one of the practice problems that I can't seem to figure out.

2[sup:1keipplv]21[/sup:1keipplv]/[4[sup:1keipplv]4[/sup:1keipplv](4[sup:1keipplv]4[/sup:1keipplv]+4[sup:1keipplv]5[/sup:1keipplv])] = ?

I've tried simplifying it a million ways, but I can't seem to get the right answer. The book says the correct answer is 2[sup:1keipplv]5[/sup:1keipplv]/5

Any help would be greatly appreciated! Thanks!

 

[tkhunny]

Re: Exponents problems - need help!

If you're taking the DAT, you may need to try a different exam. SAT maybe? :wink:

4^4 = (2^2)^4 = 2^8

(4^4 + 4^5) = (4^4)[1+4] = (2^8)*5

Now what?

 

[shooger]

Re: Exponents problems - need help!

Got it. Thanks!