top button
Flag Notify
    Connect to us
      Facebook Login
      Site Registration Why to Join

    Get Free Puzzle Updates

Facebook Login
Site Registration

If 4^(n + 4) - 4^(n + 2) = 960, What is the value of n?

0 votes
48 views
posted May 19 by anonymous

Share this puzzle
Facebook Share Button Twitter Share Button Google+ Share Button LinkedIn Share Button Multiple Social Share Button

2 Solutions

0 votes

For this equation to be true 4^(n+4) should be just greater than 960 or in other words should be as close as possible to 960 and exceeding it. It's known that 4^(5) = 1024 therefore corresponding to this
n = 1 which means the given equation becomes
4^(1+4) - 4^(1+2) = 1024 - 64 = 960.

solution May 19 by Tejas Naik
0 votes

4 ^(n + 4) = 4^(n+2+2) = 4^2 {4^ (n+2)}
so
4^(n+4) - 4^(n+2) = 4^2 {4^ (n+2)} - 4^ (n+2) = 960........................i
facting out 4^ (n+2) eqn i becomes

4^ (n+2) [(4^2)-1] = 4^ (n+2)[16-1] = 4^ (n+2) [15] = 960................ii

dividing by 15 both sides of eqn ii

4^ (n+2) = 64 but 64 = 4^3, so
4^ (n+2) = 4^3, which makes
n+2 = 3, giving
n = 1

solution May 19 by Justine Mtafungwa



Similar Puzzles
Contact Us
+91 9880187415
sales@queryhome.net
support@queryhome.net
#470/147, 3rd Floor, 5th Main,
HSR Layout Sector 7,
Bangalore - 560102,
Karnataka INDIA.
QUERY HOME
...