Question

Hmmmmmmmmmmmmmmmmmmmmmmm

Answer 1

it's A, the one your cursor is over

Answer 2

`(7)/(14), (20)/(40)`

Explanation:

Two fractions
`(a)/(b), (c)/(d)` are said to be proportional to each when there exists a number
`k` such that

`c=ka\\d=kb`

So k must be the same for both equations.

Let's analyze the 4 pairs of fractions:

1)
`(7)/(14), (20)/(40)`

We have:

`7=k\cdot 20 \rightarrow k=(7)/(20)\\14=k\cdot 40 \rightarrow k = (14)/(40)=(7)/(20)`

k is the same, so these two fractions are proportional.

2)
`(18)/(24),(6)/(12)`

We have:

`18=k\cdot 6 \rightarrow k=(18)/(6)=3\\24=k\cdot 12 \rightarrow k = (24)/(12)=2`

k is NOT the same, so these two fractions are NOT proportional.

3)

`(6)/(21), (2)/(42)`

We have:

`6=k\cdot 2 \rightarrow k=(6)/(2)=3\\21=k\cdot 42 \rightarrow k = (21)/(42)=0.5`

k is NOT the same, so these two fractions are NOT proportional.

4)

`(25)/(100),(50)/(150)`

We have:

`25=k\cdot 50 \rightarrow k=(25)/(50)=0.5\\100=k\cdot 150 \rightarrow k = (100)/(150)=(2)/(3)`

k is NOT the same, so these two fractions are NOT proportional.