Amath teacher randomly selects one student in a class to write a probability question on a chalkboard. the teacher then randomly selects a different student to answer the probability question. there are 12 boys in the class, and the ratio of boys to girls is 2: 3. find the probability that the teacher selects a girl first and a girl second. write your answer as a decimal rounded to the nearest thousandth.

The probability that the teacher selects a girl first and a girl second is 0.352

Step-by-step explanation:

Number of boys in class = 12

let number of boys in class = 2x

number of girls in class = 3x

According to the question,

2x = 12

x = 6

So, number of girls = 3x = 3 × 6 = 18

Total number of students = 18 + 12 = 30

Probability of selecting a girl first and second girl =

Therefore, The probability that the teacher selects a girl first and a girl second is 0.352

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."