SOLUTION: Can someone help me solve this problem for an SAT practice test; 3(81/16)^-3/4 I have the answer but don't know how they got it. The answer is 8/9. Thanks

Algebra ->  Exponents-negative-and-fractional -> SOLUTION: Can someone help me solve this problem for an SAT practice test; 3(81/16)^-3/4 I have the answer but don't know how they got it. The answer is 8/9. Thanks      Log On


   

Question 348001: Can someone help me solve this problem for an SAT practice test;
3(81/16)^-3/4
I have the answer but don't know how they got it.
The answer is 8/9.
Thanks
Found 2 solutions by jim_thompson5910, checkley77:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!



So 3%2881%2F16%29%5E%28-3%2F4%29%5E%22%22=8%2F9


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
3(81/16)^-3/4
The exponent (-3.4) changes the term (81/16) to the denominator with positive exponents.
3(1/[fourthrt(81/16)^3] cube the (81/16) term.
3/[fourthrt(532,441/4,096)]find the 4 th root of (532,441/4096)
3/[27/8]) invert the denominator (27/81) & multiply.
3*8/27=24/27=8/9 ans.