+11912 seventy coins of 10 paisa and 50 paisa are mixed in a purse . if the total value of the money in the purse is 19 rs find the number of each type of coins ?
+33654 Let n be the number of 10 paisa coins and m the number of 50 paisa coins.
We are told
n + m = 70 ...(1)
10*n + 50*m = 19*100 ...(2) (if, that is, the r stands for rupees and there are 100 paisa in 1 rupee).
Rearrange equation (1) to get
n = 70 - m ...(3)
Substitute this into equation (2):
10*(70 - m) + 50*m = 19*100
Multiply out the bracketed term
700 - 10*m +50*m = 19*100
Collect the m's
700 +40*m = 19*100
Subtract 700 from both sides
40*m = 1200
Divide both sides by 40
m = 30
Substitute this back into equation (3)
n = 70 - 30
n = 40
+33654 Let n be the number of 10 paisa coins and m the number of 50 paisa coins.
We are told
n + m = 70 ...(1)
10*n + 50*m = 19*100 ...(2) (if, that is, the r stands for rupees and there are 100 paisa in 1 rupee).
Rearrange equation (1) to get
n = 70 - m ...(3)
Substitute this into equation (2):
10*(70 - m) + 50*m = 19*100
Multiply out the bracketed term
700 - 10*m +50*m = 19*100
Collect the m's
700 +40*m = 19*100
Subtract 700 from both sides
40*m = 1200
Divide both sides by 40
m = 30
Substitute this back into equation (3)
n = 70 - 30
n = 40
