The municipal committee makes decision to build 50 housing units for low income families. The housing units come in 3 kinds, A, B and C. Kind A units will cost $500k each to build and will give city with revenue from rental payments of amount $25k per year. Corresponding numbers for kind B units are $625k and $30k per year, and numbers for kind C units are $400k and $22.5k per year. If total cost to build 50 units was $24,750,000; and yearly revenue from rental payments is $1,262,500; how many of every kinds of unit was built by city?