a If you add 2 ounces of 40F cream to the 180F coffee in the cup how long will

A if you add 2 ounces of 40f cream to the 180f coffee

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(a) If you add 2 ounces of 40°F cream to the 180°F coffee in the cup, how long will it take for the mixture to reach drinking temperature? Give your answer (in minutes) in decimal form with at least 3 decimal digits (for example, 12.345 minutes). 16.033 16.03261 minutes (b) If you let the 12 ounces of 180°F coffee cool for 5 minutes before adding 2 ounces of 40°F cream, how long will it take (after the initial time when the coffee was 180°F) for the mixture to reach drinking temperature? Give your answer (in minutes) in decimal form with at least 3 decimal digits (for example, 12.345 minutes). 15.760 15.75983 minutes (c) In order to reach drinking temperature as quickly as possible, should you add the cream immediately, or wait 5 minutes? you should add the cream immediately you should wait 5 minutes
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11/17/14, 2:19 PM Math 125 HW_9C Page 8 of 8 7. 9/9 points | Previous Answers A person borrows $10,000 and repays the loan at the rate of $2,400 per year. The lender charges interest of 10% per year. Assuming the payments are made continuously and interest is compounded continuously (a pretty good approximation to reality for long-term loans), the amount M ( t ) of money (in dollars) owed t years after the loan is made satisfies the differential equation and the initial condition (a) Solve this initial-value problem for M ( t ). M ( t ) = (b) How long does it take to pay off the loan? That is, at what time t is M ( t ) = 0? Give your answer (in years) in decimal form with at least 3 decimal digits. 5.390 5.389965 years = M 2400 dM dt 1 10 M (0) = 10000.
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