Answer:
the Rule of 72 is also used to determine how long it takes for money to halve in value for a given rate of inflation
Step-by-step explanation:
sorry idk other question
Answer:
2.35%
Step-by-step explanation:
Mean number of months (M) = 39 months
Standard deviation (S) = 10 months
According to the 68-95-99.7 rule, 95% of the data is comprised within two standard deviations of the mean (39-20 to 39+20 months), while 99.7% of the data is comprised within two standard deviations of the mean (39-30 to 39+30 months).
Therefore, the percentage of cars still in service from 59 to 69 months is:

The approximate percentage of cars that remain in service between 59 and 69 months is 2.35%.
Answer:
2 out of 10 or 2/10
Step-by-step explanation:
1 brown shoes + 7 black shoes = 8
that means there were 2 other students wearing neither so out of the 10 students 2 weren't wearing black or brown shoes making 2/10
For example:
x+2y=7
6x+7y=2
__________
x=7-2y *
6*(7-2y)+7y=2 **
__________
x=7-2y
42-12y+7y=2
__________
x=7-2y
-5y=-40
__________
x=7-2y
y=8
x=-9