our lesson is about finding the time in a compound interest problem. we need to present this to our math class... I tried the formula taught to us by our math teacher but the result seem unreasonable... i need help from you guys.
Answers (1)
If the principal is P then at the end of one interest period it will have accrued to P x 1.12. At the end of two periods it will be P x (1.12)^2. At the end of N periods it will be P x (1.12)^N. Now plug in the given numbers.
2500 = 600 x (1.12)^N The rule is you can do any valid operation on both sides of an equation and it will still be equal. Divide by 600.
4.167 = (1.12)^N
log(4.167) = N x log(1.12)
N = log(4.167)/log(1.12)
N = 12.593
Check: 600 x (1.12)^12.593 = 2500.079447
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