// Numbas version: exam_results_page_options {"name": "Future Value - Annuity 1", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"functions": {}, "ungrouped_variables": ["R", "perc", "perc2", "int", "num", "years", "n", "num2", "num3", "A"], "name": "Future Value - Annuity 1", "tags": ["future value", "rebel", "REBEL", "Rebel", "rebelmaths"], "advice": "

The future value of an annuity, $A$ is given by:

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$A=\\frac{R[(1+i)^n-1]}{i}$

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where $R$ represents the periodic payment, $i$ represents the interest rate per period and $n$ represents the number of payments. 

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$A$ represents the future value of the annuity, this is what we are asked to calculate.

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$i$ represents the rate of compound interest. the annual interest rate is $\\var{perc}$% so the monthly rate of interest is $\\frac {\\var{perc}} {12}=\\var{perc2}$% and therefore $i=\\frac{\\var{perc2}}{100}=\\var{int}$.

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$n$ represents the number of payments, there are 12 payments over $\\var{years}$ year(s) so $n$ is $12 \\times \\var{years}=\\var{n}$.

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The value of each repayment, is €$\\var{R}$ 

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Using the formula:

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$A=\\frac{R[(1+i)^n-1]}{i}$

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$A=\\frac{\\var{R}[(1+\\var{int})^{\\var{n}}-1]}{\\var{int}}$

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$A=\\frac{\\var{R}[\\var{num}-1]}{\\var{int}}$

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$A=\\frac{\\var{R}[\\var{num2}]}{\\var{int}}$

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$A = \\var{R} \\times \\var{num3}$

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$A=\\var{A}$

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What is the future value of the annuity in $\\var{years}$ years?

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€[[0]]

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To provide for retirement an employee deposits €$\\var{R}$ at the end of each month into an account that earns $\\var{perc}$% annual interest compounded monthly. 

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To provide for retirement an employee deposits R at the end of each month in an account that earns $perc% annual interest compound monthly. What is the future value of the annuity in nyears?

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rebelmaths

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