Question

a lady went to a bank with rs.1 lakh . she asks the cashier to gave her rupees 500 and 1000 rupess currency notes in return . she got 175 notes in all . find the number of each type of currency notes

Answer 1

hey mate
let the no of 500 notes be 500x
and the no of 1000 notes is 1000(175-x)
then,500x+1000(175-x)=100000.
then,500x+175000-1000x=100000
then, -500x=-75000
then,x=150
so,no of 500 notes =x=150
and no of 1000 notes=(175-x)=175-150=25

Answer 2

Let the no. of Rs.500 currency notes is x and of Rs.1000 currency notes is y.



A/Q,

x + y = 175 -------- ( 1 )

And,

RS.500x + RS.1000y = RS.1,00,000


RS. 500 ( x + 2y ) = RS. 1,00,000

x + 2y = RS. 1,00,000 ÷ RS. 500

x + 2y = 200 ------- ( 2 )


By subtracting ( 1 ) from ( 2 ),

( x + 2y ) - ( x + y ) = 200 - 175

x + 2y - x - y = 25

y = 25.


By substituting the value of y in ( 1 ),

x + y = 175

x + 25 = 175

x = 175 - 25

x = 150.


No. of currency notes of RS.500 is 150 and of RS.1000 is 25.



Hope it helps !!