A man purchased 47 stamps of 20 p and 25 p for Z 10. Find the number of each type of stamps.
Let us assume the number of stamps of 20p and 25p be x and y respectively
According to the question, we have
x + y = 47 …(i)
0.20x + 0.25y = 10
Also, 4x + 5y = 200 …(ii)
From equation (i), we have
y = 47 – x
Now, putting the value of y in (ii), we get
4x + 5 (47 – x) = 200
4x – 5x + 235 = 200
x = 235 – 200
x = 35
Now putting the value of x in (i), we get:
35 + y = 47
∴ y = 47 – 35
y = 12
Hence, the number of 20p stamps are 35 and the number of 25p stamps are 12