For this case the first thing you should do is find the percentage of sunglasses that are defective.
For this, we make the following rule of three:
60 pairs -------------------> 100%
5 pairs ---------------------> x
From here, we clear the value of x.
We have then:
[tex] x = (\frac{5}{60}) * (100)
x = 8.3%
[/tex]
We now look for the amount of sunglasses that may come with defects.
We have then:
[tex] N = (0.083) * (420)
N = 34.86
[/tex]
Rounding to the nearest whole number:
[tex] N = 35
[/tex]
Answer:
About 35 defective pairs will be in a shipment of 420 sunglasses
