Mary wanted to know the amount of time 7th grade students spend on homework each week, so she surveyed 20 students at random. There are 164 students in the 7th grade. Predict how many 7th grade students spend 5 hours on homework in a week

hello from mrbilldoesmath!

answer:

(7 x + 6 y) (49 x^2 - 42 x y + 36 y^2)

discussion:

the trick is to recognize that 343 = 7^3 and 216 = 6^3 and, in general,

a^3 + b^3 =   (a + b) (a^2 - a b + b^2).

in our case

343x^3+216y^3   =   (7x)^3 + (6y)^3

so take a = 7x and b = 6y in the above equation to get the answer.

you,

mrb

25.3

step-by-step explanation:

1st step

add 3+6

=9

multipy 9*3

=37