Posted by **victoria** on Monday, April 19, 2010 at 11:26am.

A used car dealership has found that the length of time before a major repair is required on the cars it sells is normally distributed with a mean of 10 months and a standard deviation of 3 months. If the dealer wants only 5 percent of the cars to fail before the end of the guarantee period for how many months should the cars be guaranteed?

- statistics -
**MathGuru**, Monday, April 19, 2010 at 8:52pm
You will need to find the z-score using a z-table. Remember the question is asking that the dealer wants only 5% of the cars to fail. Keep that in mind when looking for the z-score.

z = (x - mean)/sd -->z-score formula

Substitute the z-score you found, the mean, and the standard deviation into the formula, then solve for x.

I'll let you take it from there.

## Answer this Question

## Related Questions

- statistics - The number of cars sold annually by used car salespeople is ...
- statistic - the academic staff of a large university are provided with a PC each...
- statistics - The duration of time it takes General Motors to build a car is ...
- Statistics - . A certain company makes 12-volt car batteries. After many years ...
- statistics - A survey found that women's heights are normally distributed with ...
- Statistics - A certain company makes 12-volt car batteries. After many years of ...
- Statistics - The lifetime of television produced by the Hishobi Company are ...
- statistics - Please let me know if I solved this right The lifetime of ...
- probability - 1. The time it takes a student to cycle to school is normally ...
- math - In a car repair shop there are 50 cars to be repaired . It is estimated ...

More Related Questions