Amarble factory produces marbles that weigh 10 grams apiece. the standard deviation of the weight of a bag of 100 marbles is 20 grams. you buy a bag of 100 marbles that weighs 960 grams.
you are 95% sure that the bag of marbles you purchased did not come from the factory.
true
false

True

Step-by-step explanation:

Given that A marble factory produces marbles that weigh 10 grams apiece.

The std deviation is 20 grams for a bag of 100 marbles.

Sample is the bag purchased

Sample weight = 960 grams

Population weight (given by factory) = 1000 gms.

Difference = sample weight -population weight = -40 gm

Std dev for 100 marbles = 20 gram

=-2

Z critical value for 95% =1.96

Since our Z lies outside -1.96 and 1.96 we cannot be 95% sure that the bag of marbles you purchased did not come from the factory.