Question

Jamal and Keisha each earn money by washing cars and mowing lawns.

Jamal can mow 4 lawns or wash 8 cars in one day. Keisha can mow 3 lawns or wash 9 cars in one day. They both charge $25 for each lawn and $15 for each car.

The chart shows their production after 3 days.

A 3-column table has 2 rows. The first column has entries Lawns, cars. The second column is labeled Jamal with entries 12, 24. The third column is labeled Keisha with entries 9, 27.

Jamal and Keisha are considering entering into an agreement to trade tasks.

How can specialization of labor benefit Jamal and Keisha? Check all that apply.

Jamal can specialize in washing cars, because he has the comparative advantage.
Keisha can specialize in washing cars, because she has the comparative advantage.
Specialization allows them to collectively mow 3 more lawns and wash 3 more cars every three days.
Specialization allows them to collectively mow 12 more lawns and wash 27 more cars every three days.
Specialization allows them to earn more money.

Answer 1

Select:
- Keisha can specialize in washing cars, because she has the comparative advantage.
- Specialization allows them to earn more money.

Why:
- Opportunity costs (per day): Jamal: 4 lawns or 8 cars → 1 lawn costs 2 cars (1 car costs 0.5 lawn). Keisha: 3 lawns or 9 cars → 1 lawn costs 3 cars (1 car costs 1/3 lawn). Keisha has the lower opportunity cost of washing cars, so she has the comparative advantage in cars; Jamal has the comparative advantage in mowing lawns.
- With specialization (Jamal mows only, Keisha washes only) in 3 days they produce Jamal: 12 lawns, Keisha: 27 cars. That combined output can be traded so both are better off and their combined earnings rise. Example: if instead they split time equally over 3 days, combined earnings are $645; if Jamal mows and Keisha washes, combined earnings are $705 — a gain of $60.

The numeric statements about “3 more” or “12 more / 27 more” are not generally correct without a specified initial allocation, so they should not be checked.