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NO LINKS!! Please help me with this problem​

NO LINKS!! Please help me with this problem​-example-1
User Allov
by
4.9k points

2 Answers

5 votes

Used formula


\boxed{\sf A=P(1+(r)/(n))^(nt)}


\\ \implies \sf 1200=600\left(1.0025\right)^(12t)


\\ \implies \sf (1200)/(600)=\left(1.0025\right)^(12t)


\\ \implies \sf 2=\left(1.0025\right)^(12t)

  • Apply natural logarithm on both sides


\implies \sf \ln 2=\ln \left(1.0025\right)^(12t)


\\ \implies \sf \ln 2=12t\ln \left(1.0025\right)


\\ \implies t=( \ln 2)/(12 \ln (1.0025))


\\ \implies t=23.1years

User Stypox
by
4.8k points
6 votes

Answer:

23.1 years (nearest tenth)

Explanation:

Compound Interest Formula


\large \text{$ \sf A=P\left(1+(r)/(n)\right)^(nt) $}

where:

  • A = final amount
  • P = principal amount
  • r = interest rate (in decimal form)
  • n = number of times interest applied per time period
  • t = number of time periods elapsed

Given:

  • A = $1200
  • P = $600
  • r = 3% = 0.03
  • n = 12 (as compounded monthly)
  • t = years

Substitute the given values into the formula and solve for t:


\implies \sf 1200=600\left(1+(0.03)/(12)\right)^(12t)


\implies \sf 1200=600\left(1.0025\right)^(12t)


\implies \sf (1200)/(600)=\left(1.0025\right)^(12t)


\implies \sf 2=\left(1.0025\right)^(12t)

Take natural logs:


\implies \sf \ln 2=\ln \left(1.0025\right)^(12t)


\implies \sf \ln 2=12t\ln \left(1.0025\right)


\implies t=( \ln 2)/(12 \ln (1.0025))


\implies t=23.13377513...


\implies t=23.1\: \sf years \:\:(nearest\:tenth)

The money will double in value in approximately
\boxed{\sf 23.1} years.

User Douwe
by
5.1k points