Question

Every day, Navya's teacher randomly picks a number from 1 to 100 to be the number of the day. Thenumber of the day can be repeated. There are 180 days in the school year. Predict how many days thenumber of the day will be greater than 75.

Answer 1

The probability of a particular outcome to happen can be calculated by

`P(\text{outcome) = }\frac{Number\text{ of required outcomes}}{\text{Number of possible outcomes}}`

In this case, the total number of possible outcomes is 100.

The numbers greater than 75 are 25.

Therefore, we can calculate the probability of having a number greater than 75 as

`P(\text{number greater than 25) = }(25)/(100)=(1)/(4)`

There are 180 days in a school year.

Hence, the number of days in the school year where the number picked will be greater than 25 can be calculated as

`\begin{gathered} \text{Number of days in school year }*\text{ Probability of number greater than 75} \\ =180*(1)/(4) \\ =45 \end{gathered}`

Therefore, there could be 45 days where the number of the day would be greater than 75.