gmatee wrote:

thanks tiger, but the question now is changed to : is 6^15 > 7^4 + 9^3 ?it is tough for me too

Thats much easier: Its true that 6^15 > 7^4 + 9^3 because 6^15 is way larger than (7^4 + 9^3).

It is always true that n^(n+1) > (n+1)^n for all n>2.

Moreover, the issue here is not of addition rather multiplication. In that case, 6^15 is way greater than (7^4 * 9^3).

Therefore, 6^15 is undoubtdly even greater than (7^4 + 9^3).

_________________

Verbal: new-to-the-verbal-forum-please-read-this-first-77546.html

Math: new-to-the-math-forum-please-read-this-first-77764.html

Gmat: everything-you-need-to-prepare-for-the-gmat-revised-77983.html

GT