David took out all his coins in his piggy bank. They were made up of only fifty cents and twenty cents coin. There are 12 fifty cents coins more than twenty cents coin. The total value of fifty cents coin is 21$ more than the total value of twenty cents coin . Find the number of fifty cents coin

3 answers

60cent coins
Can you please give step by step explaination
number of twenty-cent coins --- x
number of fifty-cent coins ----- x+12

value of x+12 fifty-cent coins = 50(x+12)
value of x twenty-cent coins = 20x

50(x+12) - 20x = 2100
50x + 600 - 20x = 2100
30x = 1500
x = 50

There are 50 twenty-cent coins
and 62 fifty cent coins


check:
value of 62 fifty-cent coins = 31
value of 50 twenty-cent coins = 10
which is a difference of 21$