Question

The percentage of working mothers y can be modeled by the equation y=0.0102x + 0.644 where x is the number of years since 1990. In what year will 90% of mothers be in the labor force?

Answer 1

it is given that 'y' is 90%
rewriting the equation using this value gives 0.9 = 0.0102x + 0.644
now simply solve for x

Answer 2

2015