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Calculate the interest accrued in a savings account, given the initial balance and annual interest rate.

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Suppose you put £{money} into a savings account exactly {years} years ago and you haven't touched the money since. The simple interest rate on the account is {perc2}% per year.

", "variables": {"perc2": {"name": "perc2", "group": "Ungrouped variables", "templateType": "anything", "description": "", "definition": "random(0..2.5 #0.05)"}, "money": {"name": "money", "group": "Ungrouped variables", "templateType": "anything", "description": "", "definition": "random(100..5000 #100)"}, "years": {"name": "years", "group": "Ungrouped variables", "templateType": "anything", "description": "", "definition": "random(2..6)"}}, "tags": ["interests", "percentages", "taxonomy"], "ungrouped_variables": ["perc2", "money", "years"], "functions": {}, "name": "Simple interest", "preamble": {"js": "", "css": ""}, "extensions": [], "advice": "

This is simple interest, which means the amount added each year is a percentage of the original amount. The amount we add is fixed for all {years} years.

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First, we work out the amount of interest for one year:

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\\begin{align}
\\var{perc2} \\text{% of } \\var{money} &= \\frac{\\var{perc2}}{100} \\times \\var{money} \\\\
&= \\var{perc2/100} \\times \\var{money} \\\\
&= £\\var{dpformat(perc2/100*money,2)} \\text{.}
\\end{align}

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The money has been in the account for {years} years, so we multiply $£\\var{dpformat(perc2/100*money,2)}$ by $\\var{years}$.

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\$£\\var{dpformat(perc2/100*money,2)} \\times \\var{years} = £\\var{dpformat(perc2/100*money*years,2)} \\text{.} \$

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Adding this to the original balance:

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\$£\\var{money} + £\\var{dpformat(perc2/100*money*years,2)} = £\\var{dpformat(perc2/100*money*years + money,2)} \\text{.} \$

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This is the amount we would get if we withdrew the whole savings balance today.

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If you were to withdraw the money from this account now, how much would you have?

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£ [[0]]

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