Question

Please help me! A spinner with equal sections numbered from 1 to 5 is spun twice. Raul is finding the probability that both spins will result in an even number. Find his mistake and correct it. He did 2/5*1/4 = 2/20

Answer 1

His mistake is that he didn't need to remove one even number on the spinner, so we just need to take 2/5×1/5=2/25.

Answer 2

Answer and Explanation:

Given : A spinner with equal sections numbered from 1 to 5 is spun twice. Raul is finding the probability that both spins will result in an even number.

He did  $\frac{2}{5}\times \frac{1}{4}=\frac{2}{20}$            

To find : His mistake and correct it ?

Solution :

Outcomes = {1,2,3,4,5}        

Total outcomes = 5

Even number = {2,4}        

Favorable outcome of getting even number = 2

Probability of getting an even number is $\frac{2}{5}$

When he spin twice there is no change in probability.

So, The probability that both spins will result in an even number is

$P=\frac{2}{5}\times \frac{2}{5}$

$P=\frac{4}{25}$

The mistake in Rahul's calculation is he apply replacement which is not applied in this.