Your company is producing special battery packs for the most popular toy during the holiday season. The life span of the battery pack is known to be Normally distributed with a mean of 250 hours and a standard deviation of 20 hours. What percentage of battery packs lasts longer than 260 hours

Step-by-step explanation:

Since the life span of the battery pack is known to be Normally distributed, we would apply the formula for normal distribution which is expressed as

z = (x - µ) / σ

Where

x = life spans of battery packs.

µ = mean life span

σ = standard deviation

From the information given,

µ = 250 hours

σ = 20 hours

The probability that a battery pack lasts longer than 260 hours. It is expressed as

P (x > 260) = 1 - P (x ≤ 260)

For x = 260

z = (260 - 250) / 20 = 0.5

Looking at the normal distribution table, the probability corresponding to the z score is 0.69

The percentage of battery packs that lasts longer than 260 hours is

0.69 * 100 = 69%