Question

factory makes car batteries. The probability that a battery is defective is 1/14. If 400 batteries are tested, about how many are expected to be defective?A) 14B) 371C) 29D)35

Answer 1

To be able to determine how many batteries are expected to be defective, we will be applying ratios and proportions:

`\text{ }(1)/(14)\text{ = }(x)/(400)`

Where,

x = the number of batteries expected to be defective

We get,

`\text{ }(1)/(14)\text{ = }(x)/(400)`
`\text{ }\frac{1\text{ x 400}}{14}\text{ = }x`
`\text{ }(400)/(14)\text{ = x}`
`28.57142857142857\text{ = x}`
`\text{ 29 }\approx\text{ x}`