Im studying finite maths right now, and i came across this question which is rather difficult...i would like some help in solving this question

A manufacturer has three divisions, which produce electricity, steel and petrol. To produce $1 of electricity, the division needs $0.02 worth of electricity, $0.20 worth of steel and $0.10 worth of petrol. To produce $1 of steel, the division needs $0.02 worth of electricity, $0.01 worth of steel and $0.02 worth of petrol. To produce $1 of petrol, the division needs $0.10 worth of electricity, $0.01 worth of petrol. The manufacturer estimates the sales demand to be $300 million for the electricity division, $100 million for the steel division and $200 million for the petrol division. At what level should each division produce in order to satisfy this demand?

thanks in advanced =D