Starting from what I know (the difference between ribbons), I decided to go from the bottom and work my way up. I then noticed a pattern (each sum was three more of the previous one), and decided to keep my pattern of the three numbers but not have to do any major mental work and instead add three to the previous sum until I got to 38.
First, note that
Then use the formula for the sum of perfect cubes:

Therefore,

The quadratic trinomial
couldn't be factored anymore, so the expression
has two factors
and
Answer: correct choice is A.
Answer:
6
Step-by-step explanation:
it would be six in one hour he would clean 2 houses in two 4 houses then in three it would be six
Answer:
r = 6 in
Step-by-step explanation:
=
r²h/3 = 216
r² (18/3) = 6 r² = 216
r² = 216/6 = 36
r = 6