Answer:
Keiko have $31 in her wallet.
David have $25 in his wallet.
Tony have $50 in his wallet.
Explanation:
Keiko
Let x = the amount in Keiko’s wallet.
David
David has $6 less than Keiko .
x - 6
Tony
Tony has has two times what David has.
2(x - 6)
The total sum of their money = 106
Keiko
x + x - 6 + 2(x - 6) = 106
2x - 6 + 2x - 12 = 106
4x - 18 = 106
4x = 106 + 18
4x /4 = 124/4
x = 31
Therefore Keiko have $31 in her wallet.
David
x - 6
31 - 6 = 25
Therefore David have $25 in his wallet.
Tony
2(x - 6)
2(31 - 6)
2(25) = 50
Therefore Tony have $50 in his wallet.
To check your work out
31 + 25 + 50 = 106