Question

a sum of rupees 500 is in the form of 5 rupee and 10 rupee notes if the total number of nodes is 75 find the number of notes of each type

Answer 1

let no. of 5 rupee note = x
let no. of 10 rupee note = y

acc. to 1st condition
5x +10y= 500
5(x + 2y) = 5(100)

x+2y = 100 ----(1)


acc. to 2nd condition
x + y = 75 –-----(2)


subtracting equation (2) from (1) , we get :
y = 15

puting value y = 15 in eq (2) , we get
x =60

so no. of 5 rupee note is 60
no. of 10 rupee note is 15