Question

In a batch of 890 calculators, 12 were found to be defective. What is the probability that a calculator chosen at random will be defective?

Answer 1

The probability of choosing a defective calculator at random would be `12/890` (or `~~1.35%`).

Explanation:

The reason why the probability of choosing a defective calculator is `12/890` is because as stated in the problem, `12` calculators would be defective out of `890`, thus the ratio would be `12` to `890`.

Note: Some people might want to simplify the fraction, however if you simplify `12/890` into `6/445` then you not would be telling the whole story.

Finally, to get `1.35%` you can write the following proportion.

`12/890=x/100`

Multiply `12` by `100` and `890` by `x`. After that you should get the following:

`890x=1200` Divide by `890`

`x=1.3483146057413033707...`