Body Building Month
An amateur bodybuilder is looking for supplement protein bars to build his muscle fast, and there are 2 available products: protein bar A and protein bar B.
Each protein bar A contains 15 g of protein and 30 g of carbohydrates and has total 200 calories. On the other hand, each protein bar B contains 30 g of protein and 20 g of carbohydrates and has total 240 calories.
According to his nutritional plan, this bodybuilder needs at least 20,000 calories from these supplements over the month, which must comprise of at least 1,800 g of protein and at least 2,200 g of carbohydrates.
If each protein bar A costs $3 and each protein bar B costs $4, what is the least possible amount of money (in $) he can spend to meet all his one-month requirements?