A manufacturer knows that their items have a normally distributed lifespan, with a mean of 5.8 years, and standard deviation of 1.7 years. The 10% of items with the shortest lifespan will last less than how many years?

3.6 years

Step-by-step explanation:

Using the standard normal probability distribution table, we obtain the Zscore which is 10% to left of the distribution.

The Zscore gives, - 1.282

To obtain the number of years, let this be x ;

Recall, the Zscore formula :

Zscore = (x - μ) / σ

x = number of years

μ = 5.8

σ = 1.7

Zscore = (x - μ) / σ

-1.282 = (x - 5.8) / 1.7

-1.282 * 1.7 = x - 5.8

-2.1794 = x - 5.8

-2.1794 + 5.8 = x

x = 3.6206

x = 3.6 years

the answer is 200

step-by-step explanation:

the way the question is worded, it seems to imply the $264 interest is simple interest, not compound interest.

the simple interest for 2 years is $264; the simple interest for 1 year is $132.

$132 interest on a $600 investment means an interest rate of (132/600)*100 = 22%.

the value of $200 at 22% interest compounded annually for three years is

200%281.22%29%5e3

the amount of interest is that value, minus the original $200.