Answer: -$100
Step-by-step explanation:
Assuming that that child care is tax deductible and that child care at home is NOT imputed and taxed then we shall tax the earnings and deduct child care from it.
The couple makes $20 per week per 40 hour week.
= 20 * 40
= $800
Marginal tax rate is 50% so,
= 800 * 50%
= $400
After tax addition is $400
Childcare is $10 per hour for 50 (not 40) hours per week so,
= 10 * 50
= $500
After-Child-Care Contribution is,
= 400 - 500
= -$100
The after-tax, after-child-care addition to family income of the spouse working each week is -$100