Question

Using the data given in the table above, find the value of a and b.

• A. a = 8%, b = ₹90
• B. a = 4%, b = ₹45
• C. a = 8%, b = ₹45
• D. a = 4%, b = ₹90

Answer 1

The correct option is D a = 4%, b = ₹90

$\text{Simple interest (S.I.)}=\frac{P\times R\times T}{100}$
where,
$P$ = Principal amount
$R$ = Rate of interest in $\%$
$T$ = Time taken in years.

For first case:
Principal amount,$P=₹750$
$R=a\%$ and $T=2years$
Simple interest amount $S.I.=₹60$

Putting the values in the formula we have,
$S.I.=\frac{750\times R\times 2}{100}$
$\Rightarrow 60=15\times R$
$\Rightarrow R=4$

So, $a=4\%$

Similarly for second case:
Principal amount,$P=₹1500$
$R=6\%$ and $T=1year$
Simple interest amount $S.I.=₹b$

Putting the values in the formula we have,
$S.I.=\frac{1500\times 6\times 1}{100}$
$\Rightarrow S.I.=₹90$

So, $b=₹90$

Hence,
$a=4\%$ and $b=₹90$