Answer:
The probability that it will weigh more than 904 grams = 0.9452
Step-by-step explanation:
Given -
Mean
= 920 grams
Standard deviation
=10
Let X be the weight of a certain brand of adult cereal
if we select one box of cereal at random from this population
The probability that it will weigh more than 904 grams =
= 
=
Putting 
=
Using Z table
= 1 - .0548
= 0.9452
4/6 can reduce to 2/3. (divide each by 2)
14/21 can reduce to 2/3 by dividing the nume/denominator by 7.
in this case, they are proportional.