Question

1. At what rate per cent will a sum of 64,000 be compounded to 68,921 in three
years?
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Answer 1

P= Principal in ₹

R= rate of interest in %

n= time period in years


Given:

A= ₹68921, P= ₹64000, n= years

A= P( 1+ R/100)^n

68921 = 64000 (1+ R/100)³

68921/64000 = (1+R/100)³

(41/40)³ = (1+R/100)³

[68921= 41³, 64000= 40³]

41/40 = (1+R/100)

41/40 - 1= R/100

(41-40)/40 = R/100

1/40 = R/100

40R= 100

R= 100/40= 10/4= 5/2= 2.5%

R= 2.5%


Rate percent = 2.5%

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Hope this will help you...