Tiles have weights that are independently normally distributed with a mean of 45.3 and a standard deviation of 0.02. What is the probability that the total weight of three tiles is no more than 135.975.

Question

ganeshie8 · Answer

so basically we need tofind :
$P(x_1 + x_2 + x_3 \le   135.975)$

anonymous · Answer

Yep.

anonymous · Answer

I tried fininding just the probability of 1 tile but that didn't work. I would multiply that probability by 3 but that wont work.

ganeshie8 · Answer

average value will do

ganeshie8 · Answer

finding    $P(x_1 + x_2 + x_3 \le   135.975)$  is same as finding below :

$\large     P(\overline{x} \le   \frac{135.975}{3}) $

anonymous · Answer

That's what I did!!

ganeshie8 · Answer

$\overline{x}$ is the average weight

anonymous · Answer

But my probability i over 100% :( .

ganeshie8 · Answer

lets see..

anonymous · Answer

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