Question

A number line contains points Q, R, S, and T. Point Q is on the coordinate 4, R is on the coordinate 8, S is on the coordinate 9, T is on the coordinate 12. Find the probability that a point chosen at random on QT is on ST. Express your answer as a percent.

A) 25%
B) 37.5%
C) 44%
D) 51.5%

Answer 1

length of ST / length of QT

3/8

Answer 2

B. 37.5%

Explanation:

We are given that,

Co-ordinate of point Q = 4

Co-ordinate of point R = 8

Co-ordinate of point S = 9

Co-ordinate of point T = 12

It is required to find the probability of a point chosen at random on QT which lies on ST.

So, we have,

Distance of line QT = 12 - 4 = 8

Distance of line ST = 12 - 9 = 3

Then, the required probability =
`(3)/(8)` = 0.375 or 37.5%

Hence, the probability of a point chosen at random on QT which lies on ST is 37.5%