Question
Alice is three times as old as Jack. In 10 years she will be twice as old as Jack. How old are Alice and Jack now? How old will they be in10 years
Answers
PsyDAG
A = 3J
A + 10 = 2(J + 10)
Substitute 3J for A in second equation and solve for J. Insert that value into the first equation and solve for A. Check by inserting both values into the second equation.
A + 10 = 2(J + 10)
Substitute 3J for A in second equation and solve for J. Insert that value into the first equation and solve for A. Check by inserting both values into the second equation.
ange
12
Nat
Jack=10 years old and Alice 30 years old