The rule of 72 is an approximate estimate of the time it takes to double an investment, and depends only on the interest rate. So amount of deposit does not change the estimate. All three accounts will take the same time to double.
If the accounts are all deposited on the same day with the same interest rate and same compounding period, they all double at the same time, whether using the rule of 72 or the actual time.
The sample space for the 3 different music CDs is as follows:
{JPR, JRP, PJR, PRJ, RJP, RPJ}
46.75 - 0.10(46.75) = 46.75 - 4.675 = 42.075 rounds to 42.08
ur simply taking ur discounted price of $ 46.75 and subtracting 10% of 46.75....leaving u with a final price of 42.08
<span>There are 24 who like both rock and country. There are 8 who like all 3 types, and these eight have been counted under the 24. This means that the number who like rock and country but not jazz is 24 - 8 = 16.
We are given a total of 155 who like country. We subtract the 16 who like both rock and country, and are left with 139 people who like country but not rock. (It does not matter whether they like jazz or not).
The probability is 155 out of the total of 500, so 155/500 = 31/100 = 0.31.
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Answer:
She should invest 6976.74 $ principal on daughter's 12th birthday.
Explanation:
We have I = prt, where I represents simple interest, p represents principal, r represents interest rate, and t represents time in years.
Here p + I = 12,000 $
So, I = 12000-p
Interest rate r = 12% =0.12
Number of years = 18 - 12 = 6 years.
Substituting
12000-p = p x 0.12 x 6
p + 0.72 p = 12000
1.72 p = 12000
p = 6976.74 $
So, she should invest 6976.74 $ principal on daughter's 12th birthday.
