Answer:
7 years 11 months
Step-by-step explanation:
The future value formula for the value of a principal P invested at annual rate r compounded n times yearly for t years is ...
FV = P(1 +r/n)^(nt)
For the given numbers, we want to find t:
6000 = 3700(1 +.062/2)^(2t)
Dividing by 3700 and taking the logarithm, we get ...
6000/3700 = 1.031^(2t)
log(60/37) = 2t·log(1.031)
Dividing by the coefficient of t gives ...
t = log(60/37)/(2log(1.031)) ≈ 7.92 . . . . . years
It will take about 7 years 11 months for the investment to grow to $6000.
Quick answer I don't think this has an answer.
If you take the cos-1(2 sqrt(2)) your calculator should have a fit. Let's check that out. Mine certainly does. So there is something wrong with the question. If there is something to add in please do it and I will it least put an answer in the comments. As it stands, nothing will work.
If you put your calculator in radians, you will get an answer but it will not be anything resembling the choices you've listed.
If you meant sqrt(2) / 2 that would give 45o. Put it in your calculator like this 2 ^ 0.5 divided by 2 = 0.707
Cos - 1 (0.707) = 45
If the first 10 bricks come out at $ 4.5, I would be spending $ 45. The other 10 bricks come out at $ 3.5 so he would be spending $ 35. Therefore, he has $ 20 available to buy bricks at $ 2.5, which would be buying 8 additional bricks. Thus, in total, with $ 100, 28 bricks were purchased.
