Answer:
Number of 10 cent coins = 14
Number of 50 cent coins = 7
Step-by-step explanation:
Let the number of coins of 10 cents = a
and the number of coins of 50 cents = b
Total count of coins = 21
a + b = 21 ---------(1)
Value of 10 cent coins = $0.10
Value of a coins of 10 cents = 0.10a
Value of 50 cent coins = $0.50
Value of b coins of 50 cents = 0.50a
The value of these coins = $4.90
0.10a + 0.50b = 4.90
a + 5b = 49 --------(2)
By subtracting equation (1) from equation (2)
(a + 5b) - (a + b) = 49 - 21
4b = 28
b = 7
From equation (1),
a + 7 = 21
a = 21 - 7
a = 14
Therefore, number of 10 cents coins = 14
number of 50 cent coins = 7
