the bank lent 1550 Rs partly at 5% and partly at 8% per annum interest. the total interest recieved by the bank after 3 years was 300 Rs. what is the ratio of money lent at 5% to that lent at 8% ?

Asked by rajanghai.2014 | 23rd Oct, 2015, 07:25: PM

Expert Answer:

L e t space x space b e space t h e space a m o u n t space o f space m o n e y space l e n t space b y space t h e space b a n k space f o r space 5 percent sign space i n t e r e s t. A n d space 1550 space minus x space b e space t h e space a m o u n t space o f space m o n e y space l e n t space b y space t h e space b a n k space f o r space 8 percent sign space i n t e r e s t.  T o t a l space i n t e r e s t space r e c e i v e d space b y space t h e space b a n k space a f t e r space 3 space y e a r s equals R s.300 W e space k n o w space t h a t comma S i m p l e space i n t e r e s t equals fraction numerator P r i n c i p a l cross times N u m b e r space o f space Y e a r s cross times R a t e space o f space I n t e r e s t over denominator 100 end fraction  T h u s comma R s.300 equals I n t e r e s t space f r o m space R s. x space f o r space 3 space y e a r s plus I n t e r e s t space f r o m space R s. open parentheses 1550 minus x close parentheses space f o r space 3 space y e a r s rightwards double arrow R s.300 equals fraction numerator x cross times 3 cross times 5 over denominator 100 end fraction plus fraction numerator open parentheses 1550 minus x close parentheses cross times 3 cross times 8 over denominator 100 end fraction rightwards double arrow R s.300 cross times 100 equals 15 x plus 37200 minus 24 x rightwards double arrow 30000 equals 15 x plus 37200 minus 24 x rightwards double arrow 24 x minus 15 x equals 37200 minus 30000 rightwards double arrow 9 x equals 7200 rightwards double arrow x equals 7200 over 9 rightwards double arrow x equals R s.800 rightwards double arrow 1550 minus x equals 1550 minus 800 rightwards double arrow 1550 minus x equals 750 T h u s comma space t h e space r a t i o space o f space m o n e y space l e n t space a t space 5 percent sign space t o space t h a t space l e n t space a t space 8 percent sign equals fraction numerator x over denominator 1550 minus x end fraction equals 800 over 750 equals 16 over 15 rightwards double arrow space r a t i o space o f space m o n e y space l e n t space a t space 5 percent sign space t o space t h a t space l e n t space a t space 8 percent sign equals 16 colon 15

Answered by Vimala Ramamurthy | 24th Oct, 2015, 09:26: AM