Please help me with this

Two blends of tea are mixed to make a blend that will be sold at the fair. black tea sells for $2.20 per pound and orange pekoe tea sells for $3.00 per pound. how much of each should be used to obtain a 4lb blend selling for $2.50 per pound?

5,600 x 10^3 = a) 560 b) 5,000,600 c) 5,600,000 d) 56,000

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