Question 54511
2n+5n=77 becomes 7n=77, which reduces to n=11 after dividing both sides by 7.
{{{5+expr(1/3)n=2}}} becomes 15+3n=6 after multiplying both sides by 3.  Subtract 15 from sides to get 3n=-9, and divide both sides by 3 to get n=-3.
{{{9-expr(1/4)n=6}}} becomes 36-n=24 after multiplying both sides by 4.  Subtract 36 from both sides to get -n=-12, which reduces to n=12.
{{{expr(1/8)n+20=32}}} becomes n+160=256 after multiplying both sides by 8.  Subtracting 160 from sides gives us n=96.
You probably have a typo in the last equation, but you can use the same process as I've used here to solve it once you determine where the typo is.