Only two numbers less than 100 have a factor of 40: 40 (1 x 40) and 80 (2 x 40). Since 40 is a factor of both 40 and 80, 10 must also be a factor - indeed, 40 = 4 x 10 and 80 = 8 x 10.
The two number must be 40 and 80.
Answer:
504 combos
Step-by-step explanation:
Cannot use digits twice and last is '7'
9 digits for first place choice
8 digits for second place
7 digits for third place
only '7' for fourth place 9 x 8 x7 = 504 combos
The answer would be
D) 40