Question

Solve this problem please...?

Answer 1

The product of the means must be equal to the product of the extremes.

Explanation:

So we need `(15a) xx 5/14 = (2 1/7) xx (0.8)`

Lets work on each side alone first

The left (the product of the means)

`15a xx 5/14 = (15 xx 5 xxa)/14 = (75a)/14`

The right (the product of the extremes)

Note that `2 1/7 = (2xx7+1)/7 = 15/7` and `0.8 = 8/10`

So we have,

`(2 1/7)(0.8) = 15/7 xx 8/10 = (3 xx cancel(5))/7 xx 8/(2xxcancel(5)) = 24/14`

Setting the two equal to each other gets us:

`(75a)/14 = 24/14`

So we need `75a = 24` and

`a = 24/75 = 8/25`

Or, if you prefer, `x = (8 xx 4)/(25 xx 4) = 32/100 = 0.32`