Remove[a];
Do[a[n] =
AbsoluteTiming[
Module[{sum = 0, i}, For[i = 1, i <= 10^5, i++, sum += Sin[N@i]];
sum]], {n, 1, 10}];
Do[b[n] = a[n][[1]], {n, 1, 10}];
Table[b[n], {n, 1, 10}];
Mean@%

Benchmark`上下文有一大堆认真写的测试用例