Find compound interest on sum of Rs 640 at 50/3% per annum for 11/4 years.

M4maths Previous Puzzles

30 Nov 2016 Compound Interest

Find compound interest on sum of Rs 640 at 50/3% per annum for 11/4 years.

OPtion

1) Rs 345
2) Rs 265
3) Rs 513
4) Rs 260
5) Rs 252
6) Rs 255
7) Rs 263.33
8) Rs 340
9) Rs 654
10)Rs 651

Solution

Reason
Amount = Rs [640*(1+50/(3*100)^2) (1+{(¾)*(50/3) / 100}]
= Rs (640 * (7/6)*(7/6)*(9/8))
= Rs 980
CI = Rs (980-640) = Rs340

Option 8)

Correct Option: 8 Best Solution (5)

G.S.Kantharao   8 years AGO

Principle = Rs.640
Rate = 50/3%
Time 11/4 =( 2+ ¾ ) years.
Amount for 2 Years = 640[1+(50/300)]^2 =871.111
Compound/simple Interest for ¾ years = (871*50*3)/(300*4) = 109 (approximately)
Total Compound Interest = 871 - 640 + 109 = 340 Hence my option is 8.

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Saurabh   8 years AGO

C.I = P*[ 1 + R ]^t - P
= [ 640 * [ 1 + ( 50/300 ) ] ^ ( 11/4 ) ] - 640
= 337.875
the nearest option is :::: 340 ----> option { 8 }

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Pragati Rode   8 years AGO

P = 640 ,R = 50/3 % N = 11/4 = 2 3/4 years

Amount =P (1+r/100)^2 * (1 + (3/4)R/100)

put all values
we get
Amount = 640 * (1+(50/3)/100)^2 * (1+ (50/3)/100)
= 640 * (7/6)^2 * (9/8)
=640 * (49/36) * (9/8)
= 980
Compound interest = 980 -640
=340
so option 8

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Mukund Manohar   8 years AGO

AMOUNT = 640 * (1+ 50/300)^2 * (1+ (3/4*50/3)/100)
= 640 * (7/6)^2 * (9/8)
= 640 * 49/36 * 9/8 = 20*7*7 = 980
CI = 980 - 640 = Rs 340

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Dinesh Sharma   8 years AGO

apply formula: A = P(1 + r/100)^t and
C.I. = A - P we get nearby 340

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