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If 30 lb of rice and 30 lb of potatoes cost ? $27.60? , and 20 lb of rice and 12 lb of potatoes cost ? $15.04? , how much will 10 lb of rice and 50 lb of potatoes? cost?

Plz ( true - false) all triangles have interior angles whose measure sum to 90.

The candy store is having a 30% off sale. emma is going to buy $7.50 worth of candy. how much will she pay after the discount