Question

Some of the children at a school arrive by car.

Answer 1

the probability that a child chosen at random from the school arrives by car is 0.74 .

Step-by-step explanation:

Here we have , Some of the children at a school arrive by car.

30% of the children at the school are boys

60% of the boys at the school arrive by car

80% of the girls at the school arrive by car

We need to find what is the probability that a child chosen at random from the school arrives by car .Let's find out:

Probability of child to arrive by car = Probability of a girl to arrive by car + Probability of a boy to arrive by car

⇒  Probability of a boy to arrive by car = $\frac{3}{10} (\frac{6}{10} )$

⇒  Probability of a boy to arrive by car = $\frac{18}{100}$

⇒  Probability of a boy to arrive by car = $0.18$

Also , Probability of a girl to arrive by car  =  $\frac{7}{10} (\frac{8}{10} )$

⇒ Probability of a girl to arrive by car = $0.56$

Putting these values we get:

⇒ $Probability = 0.56+0.18$

⇒ $Probability =0.74$

Therefore , the probability that a child chosen at random from the school arrives by car is 0.74 .

Answer 2

Answer:

0.74

Step-by-step explanation:

30% boys

So 100-30 = 70% girls

(60% × 30%) + (80% × 70%)

0.74