Select all the ratios that are equivalent to 4:5 A 2:2.5
B 2:3
C 3:3.5
D 7:8
E 8:10
F 14:27.5

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

but there’s no any figure there!

hi williamspatsy,

to find the answer we need to divide. so, 22.2(22 1/5)/8.5(8 1/2) = 2.6176470588 but, the question is asking how many full batches can she make so, that would be only 2.

hope this !

cupkake~

the answer is d d.

surface area: 4,644,025 pi

volume: 1,667,978,979 pi