Answer:
286
Step-by-step explanation:
If the three-digit number is xyz, then:
x + y + z = 16
y = z + 2
z = 3x
Substitute the third equation into the second:
y = 3x + 2
Substitute this and the third equation into the first:
x + (3x + 2) + (3x) = 16
7x + 2 = 16
7x = 14
x = 2
y = 3x + 2 = 8
z = 3x = 6
The number is 286.
25
because you have to divide by 15's
10 by 2
82 in^3
3 x 2 x 7 + 2 x 2 x 10 = 82 in^3
