Please refer to the attachment
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We have:-
[tex] \tt \: So,amount \: for \: 2 \: years = p \large(1 + \frac{r}{100}) {}^{n} [/tex]
[tex] \tt=₹26,400 \large(1 + \frac{15}{100}) {}^{2}[/tex]
[tex] \tt=₹26,400 \: \large( \frac{23}{20}) {}^{2} [/tex]
[tex] \tt =₹26,400 \times \frac{23}{20} \times \frac{23}{20} \\ [/tex]
[tex] \tt = 66 \times 529=₹34,914[/tex]
[tex] \tt \: So,SI \: for \: 4 \: months = \frac{P \times R \times n }{100 \times 12} [/tex]
[tex] \tt \: = \frac{ 34,914 \times 15 \times 4 }{100 \times 12} \\ [/tex]
[tex] \tt\boxed{ = 1745.70}[/tex]
Thus,the amount after 2years and 4months =₹34,914+₹1745.70=₹36,659.70
[tex] \bold \red{I \: hope \: this \: may \: help \: you}[/tex]