Question

Which function increases by 1/3 every time the x-increases by 1?

A) y = 3x
B) y = 3x + 1
C) y = (1/3)x
D) y = 1/3x + 1

Answer 1

it was b for me in usa test prep

Explanation:

Answer 2

C) y = (1/3)x

D) y = 1/3x + 1

Explanation:

One simple method to evaluate this question is by inserting the values of x in the options:

A) If x =1

y = 3*(1) = 3

for x =2

y = 3*(2) = 6

=> Value of function is increasing by the factor 3, so option is wrong.

B) If x =1

y = 3*(1) +1 = 4

for x =2

y = 3*(2) + 1 = 7

=> Value of function is increasing by the factor 3, so option is wrong.

C) If x =1

y = (1/3)*(1) = 1/3

for x =2

y = (1/3)*(2) = 2/3

for x =3

y = (1/3)*(3) = 3/3 = 1

=> Value of function is increasing by the factor 1/3, so option is correct.

D) If x =1

y = (1/3)*(1) + 1 = 4/3

for x =2

y = (1/3)*(2) + 1 = 5/3

for x =3

y = (1/3)*(3) +1 = 3/3 + 1 = 2

=> Value of function is increasing by the factor 1/3, so option is also correct.