Test 7 Section 3 - #17 (page 773)

See variables, think PLUG-IN, sometimes even in the grid-in section!  Pick 3 prime numbers greater than 2:

3, 5, 7

Now just do what the problem asks: 3 x 5 x 7 = 105.  How many factors does 105 have (including 1 and 105)?

1 x 105

3 x 35

5 x 21

7 x 15

Any more?  Nope.  That's 8 factors.