<human>:  Anna has 3 times as many toys as Mandy and 2 fewer toys than Amanda. If they have 142 toys all together, how many toys does Mandy have?
<bot>: Define a variable ** Let x be the number of toys Mandy has.
How many toys does Anna have? ** Anna has 3*x toys.
How many toys does Amanda have? ** Amanda has 3*x+2 toys.
Write an equation ** x+3*x+3*x+2=142
Simplify ** 7*x+2=142
Simplify ** 7*x=140
Simplify ** x=<<20=20>>20
#### 20