Savings bank interest

On March 24, we deposited €5,400 into the savings bank. How much interest will we earn until the end of the year, when the savings bank provides 4.2% interest on this type of deposit?

Final Answer:

i =  173.88 eur

Step-by-step explanation:

$$\begin{gathered} a=5400\text{eur} \\ r=4.2\%=\frac{4.2}{100}=0.042 \\ d=\frac{360-(30+30+24)}{360}=\frac{23}{30}\doteq 0.7667 \\ {r}_2=d\cdot r=0.7667\cdot 0.042=\frac{161}{5000}=0.0322 \\ i=a\cdot r_2=5400\cdot 0.0322=173.88\text{eur} \end{gathered}$$

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