If he bikes for 10 miles per hour and 8 miles per hour for the same distance x miles, he went 10 miles per hour for x/10 hours, as Distance = Rate*Time and on the way back he would go for x/8 hours. So then he went 2x distance, in x/8 + x/10 hours. Since x/8 + x/10 = 10x/80 + 8x/80 = 18x/80 = 9x/40, he went 2x miles in 9x/40 hours. this can be converted into a rate with the above equation Distance = Rate*Time, so 2x=(9x/40) * Rate, thus we divide by 9x/40 on both sides to get 80x/9x = Rate, the x cancels out, and we get 80/9 Miles per hour.
<em><u>Question:</u></em>
Juan Invest $3700 In A Simple Interest Account At A Rate Of 4% For 15 Years. How Much Money Will Be In The Account After 15 Years?
<em><u>Answer:</u></em>
There will be $ 5920 in account after 15 years
<em><u>Solution:</u></em>
<em><u>The simple interest is given by formula:</u></em>
Where,
p is the principal
n is number of years
r is rate of interest
From given,
p = 3700
r = 4 %
t = 15 years
Therefore,
<em><u>How Much Money Will Be In The Account After 15 Years?</u></em>
Total money = principal + simple interest
Total money = 3700 + 2220
Total money = 5920
Thus there will be $ 5920 in account after 15 years
Answer:
B
Step-by-step explanation:
Over time, compound interest at any rate will outperform simple interest. When the rates are nearly equal to start with, compound interest will be greater in very short order. Here, it takes less than 1 year for compound interest to give a larger account balance.
In 30 years, the simple interest will be
... I = P·r·t = 12,000·0.07·30 = 25,200
In 30 years, the compound interest will be
... I = P·(e^(rt) -1) = 12,000·(e^(.068·30) -1) ≈ 80,287.31
_____
6.8% compounded continuously results in more total interest
