Problema Solution

the simple interest "i" earned over a particular period of time varies jointly as the principal "p" and rate "r", and "i" equals $264 when "p" equals $1100 and "r" equals 0.12. find P when "I" equals $360 and "r" equals .09.

Answer provided by our tutors

The simple interest formula is I = PxrxT

For the first case;

I = 264

P = 1100

r = 0.12

 

I = PrT

264 = 1100x0.12xT

T = 264/(1100x0.12)

T = 2

 

For second case

I = 360

r = 0.09

T = 2

 

I = PrT

P = I/(Tr)

P = 360/(2x0.09)

P = 2000

 

So the principal would be $2000.