70 coins of 10paise and 50paise are kept in a purse.if the total no. money in the purse is RS.19?

The abbreviation for the Indian rupee according to the ISO-4217-code is INR.

[0] 1 INR = 100 paise

There are two unknowns x, y:
x = number of coins with the value of 10 paise each.
y = number of coins with the value of 50 paise each.

1st condition:

[1] x + y = 70

2nd condition:
The values of these 70 coins add up to 19 INR (19 INR = 1900 paise [0]).

[2] 10x + 50y = 1900

We have to solve this system of linear equations:

[3]:=([1] * 10) -> 10x + 10y = 700
[4]:=([2] - [3]) -> 40y = 1200 ;;divide by 40 to get y:

[5] y = 30

Insert this value of y into [2]:

[6]:=([2]<-[5]) -> 10x + 1500 = 1900 ;;divide by 10:
x + 150 = 190 ;;isolate x:

[7] x = 40

Verify:

[8]:=([1]<-[7, 5]) -> 40 + 30 = 70 ;; O.K.
[9]:=([2]<-(7, 5]) -> 400 + 1500 = 1900 ;;O.K.

And 1900 paise = 19 INR [0].