Question

in what time will the simple intrest on 400 at 10% per annum be the same as the simple intrest on 1000 for 4 years at 4% per annum

Answer 1

SI = (1000×4×4)/100
= 160
NOW,
SI. 160
P. 400
R. 10
THEN R = (100×160)/400×10
= 4%.