in a primary school 70% of the

boys and 55% of the girls can ride
a bicycle. if a boy or a girl are
chosen at random, what is the
probability that both of them can
ride a bicycle?

Are you choosing one or two? "boy or girl" vs. "both of them"?

If the events are independent, the probability of both/all events occurring is determined by multiplying the probabilities of the individual events.

Either-or probabilities are found by adding the individual probabilities.

Tts wat I don't get coz th question is written lyk tt

"Tts wat I don't get coz th question is written lyk tt"

Donald -- please use standard English when you post here. This is an academic message board, staffed by literate people, many of whom are certified teachers.

Ooops sorry can you now please work it out using the independent rule

The question isn't correct. It's not clear whether one or two children is chosen. Ask your teacher for clarification.

Ok thank you

To find the probability that both a boy and a girl can ride a bicycle, we need to multiply the probabilities of each event happening.

Let's break down the problem step by step.

Step 1: Find the probability that a random boy can ride a bicycle.
In a primary school, 70% of the boys can ride a bicycle. The probability of a random boy being able to ride a bicycle is 70% or 0.7.

Step 2: Find the probability that a random girl can ride a bicycle.
In the same primary school, 55% of the girls can ride a bicycle. The probability of a random girl being able to ride a bicycle is 55% or 0.55.

Step 3: Find the probability that both a boy and a girl can ride a bicycle.
Since we are choosing one boy and one girl at random, and these events are independent, we multiply the probabilities. Therefore, the probability that both a boy and a girl can ride a bicycle is:

P(boy and girl) = P(boy) × P(girl)
= 0.7 × 0.55

Calculating this gives us:
P(boy and girl) = 0.385 or 38.5%

So, the probability that both a boy and a girl can ride a bicycle is 38.5%.