Question

If y varies directly as x, and y is 180 when x is n and y is n when x is 5, what is the value of n?

6
18
30
36

Answer 1

As given

y varies directly as x

thus

y = kx

Where k is the constant of proportionality .

As given

y is 180 when x is n

180 = kn

y is n when x is 5

n = 5k

Compare the value of k .

solving

n² = 900

n = √900

n = 30

Therefore the value of n is 30 .

Explanation:

Answer 2

6

Explanation:

y=k*x

180=k*n

n=k*5

180=k*k*5. so k*k=36, k=6