Манго и папайя

Farms A, B and C produce only mangoes (M) and papayas (P). The production possibility frontier of each farm is as follows:

Farm A: $MA + PA = 100$

Farm B: $2MB + 3PB = 300$

Farm C: $MC + 2PC = 600$

What is the maximum number of mangoes that they can produce together if they want to produce at least 300 papayas?