Question

某食堂储存了a天用的煤40T,要使储存的煤比预定的天数多用2天,每天应节约用煤多少吨【先列示,再化简】?

Answer 1

节约用煤为：40/a-40/(a+2) 吨

化简：

40/a-40/(a+2)

=40x[1/a-1/(a+2)]

=40x[(a+2-a)/a(a+2)]

=40x2/a(a+2)

=80/a(a+2)