If x = 100!, y = 100!/60!, and z = 100^40 , order them from least to greatest without using a calculator.
100! / 60! = 100 * 99 * 98 * .....* 62 * 61
This is definitely smaller than 100^40
100! =
(100*99) * (98 *97) * (96 * 95) * (94 * 93) * (92 * 91) * ......* (10 * 11)
Note that we have ( 100 - 10) / 2 + 1 = 46 terms in this partial evaluation of 100!....each is > 100
So
100! > 100^40
So
1001/ 60! < 100^40 < 100!