Given: The burning time of a very large candle is normally distributed with mean $(\mu)$ of 2500 hours and standard deviation $(\sigma)$ of 20 hours.

Let X be a random variable that represent the burning time of a very large candle.

Formula: $Z=\dfrac{X-\mu}{\sigma}$

For X = 2470

$Z=\dfrac{2470-2500}{20}\\\\\Rightarrow\ Z=\dfrac{-30}{20}\\\\\Rightarrow\ Z=\dfrac{-3}{2}\\\\\Rightarrow\ Z=-1.5$

So, the z-score they corresponds to a lifespan of 2470 hours. =-1.5

Hence, the correct option is C.-1.5.

7 0

2 years ago

PLEASE HELP! I will give you the brainiest and A LOT of points! (Ch.5.3)

JulsSmile [24]

Step-by-step explanation:

Total distance covered=distance covered by walking+distance covered by jogging

=6/7+4/5=30+28/35

=58/35miles

How much farther did you walk than jog

=6/7-4/5

=30-28/35

=2/35miles

3 0

2 years ago