Question

please tell answer of question number 11 12 13

Answer 1

Dear friend,

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Q11.
P = Rs. 6500
R = ?
T = 3 yrs
A = Rs. 7930
SI = A - P = Rs. 1430

$r = \frac{si \times 100}{pt} = \frac{1430 \times 100}{6500 \times 3} = \frac{22}{3}$

Answer. Rate of interest is 22/3 p.a.

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Q12.
P = x
R = 7 % p.a.
T = 4 yrs
A = Rs. 5120
SI = A - P = 5120 - x

$p = \frac{si \times 100}{rt}$

$x = \frac{5120 - x \times 100}{7 \times 4}$

$x = \frac{25(5120 - x)}{7}$

$7x = 128000 - 25x$

$32x = 12800$

$x = \frac{12800}{32} = 4000$

Answer. The sum of money is Rs. 4000

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Q13.
P = Rs. 4500
R = 9 % p.a.
T = ?
A = Rs. 12600
SI = A - P = Rs. 8100

$t = \frac{si \times 100}{pr} = \frac{8100 \times 100}{4500 \times 9} = 20$

Answer. Time is 20 yrs.

Hope it helps !!!