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A hot - water faucet can fill a bathtub in 20 minutes; and the cold-water faucet can fill it in 10 minutes. How long will it take to fill the same bathtub with both faucets running?

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Identify a1 and r for the geometric sequence an= -256(-1/4) n-1

Giuseppi's pizza had orders for $931.00 of pizzas. the prices were $21 for a large pizza, 514 for a medium pizza, and $7 for a small pizza. the number of large pizzas was two less than four times the number of medium pizzas. thenumber of small pizzas was three more than three times the number of medium pizzas. how many of each size of pizza were ordered?

Asurvey of 2,000 doctors showed that an average of 3 out of 5 doctors use brand x aspirin.how many doctors use brand x aspirin