How does your figure look like?
d1 = 51(t)
d2 = 71(8 - t)
d1 + d2 = 508
and now you just have to solve for t.
About 10 songs because if you add up all ten numbers of all the songs then you divide, then you divide again you will get 10 songs
1.25
the exponent is to the 6th because there are six zeros
