The sum of three numbers is 20. If the first number is three times the difference between the second and the third, and the second number is two more than twice the third, find the three numbers.

Answer 1

F=3(S-T) = 3S -3T

F+S+T = 20

S= 2+ 2T

F=3(2+2T) -3T= 6+6T-3T = 6+3T

6+3T + 2+2T + T = 20

6T = 20-8 = 12

T = 12/6 = 2 = third number

S= 2+2T= 2+2(2) = 6 = second number

F=6+3T = 6+3(2) = 12 = first number