Question

At some rate of simple interest, a sum becomes Rs.690 in 3 years and Rs.750 in 5 years. The rate of interest is

Answer 1

((p*3*r)/100)+p=690

((p*5*r)/100)+p=750

so ((p*2*r)/100)=60

p*r=6000/2=3000

substituing pr=3000

p=600

r=5

hence r=5%

Answer 2

Solution :-

Given,
P = 690 RS for time period in 3 year's
P = 750 RS time period in 5 years
Rate of interest = ? ( find)


S.I. = P×R×T / 100

(P×3×R\3) + P = 690 -----------> (I)

(P × 5× R) + P = 750 ----------> (ii)

Equation (I) - (ii)

so

(P×2×R )/100=60

P×R =6000/2=3000

substituing pr=3000

P=600

R =5

hence

R =5% Ans

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@GauravSaxena01