Question

A sum of rs. 1550 was lent partly at 5% and partly at 8% simple interest. The total interest received after 3 years is rs.300. The ratio of money lent at 5% to that at 8% is:

Answer 1

Answer:

16:15

Step-by-step explanation:

total amount=1550

part 1

let Principle = P

rate=R=5%

time=T=3 years

S.I= PTR/100

=P×5×3/100

=15P/100

part 2

P=1550-P

R=8%

T=3 years

S.I=(1550-P)×3×8/100

total S.I=15P/100+(1550-P)×3×8/100

=15P/100+1550×24/100-24P/100

=372+(15P-24P)/100

given that total profit = 300

so,

372+(15P-24P)/100 = 300

(15P-24P)/100=300-372

(15P-24P)/100=-72

-9P/100=-72

P=(-72)×100/(-9)

P=800

principal for first part = 800

principal for second part = 1550-800=750

ratio of money lent in both cases = 800:750 = 16:15

hence the answer.