months she paid 3025 and settled her accounts. What amount did she borrow?
12. A sum of money doubles itself in 6 yrs. In how many years will it treble itself at the
same rate of interest?
13. Amit borrowed *1825 from a bank on March 16, 1999, at the rate of 12% per.
Give me Solution
Answers
Step-by-step explanation:
12)The sum of money doubles in 6 years means the interest for 6 years equals to original sum of money I.e. Principle. Let the Principle = P and rate of interest = r %
So, P + P * r *6/100 = 2P
Or, p*r*6/100 = 2P - P = P
Or, r = 100/6 = 16.67 %
For sum to be treble, the interest should be twice the Principle I.e. P * (16.67/1t00) * t = 2P where t is the period when the sum will be 3 times.
Or, t = 100 * 2/16.67 = 12 years. Ans.
Simply you can also give a statement that when sum is doubled in 6 years for simple interest, the sum will be tripled in 6 * 2 = 12 years
13)Amount to be paid by Amit:
SI=
100
PRT
=16000×17.5×
100
2
=Rs5600
Amount gained by Amit:
A=P(1+
100
R
)
n
A=16000(1+
100
17.5
)
2
A=50000(1.175)
2
A= Rs 22090
We know that:
CI=A–P= Rs 22090– Rs 16000= Rs 6090
Amit’s gain in the whole transaction = Rs 6090– Rs 5600= Rs 490