Q: It takes 2.5 hours to groom a dog and 0.5 hours to groom a cat. What is the number of minutes it takes to groom 5 dogs and 3 cats?
A: 2.5 * 5 = 12.5 hours. 0.5 * 3 = 1.5 hours. 12.5 + 1.5 hours = 14 hours. 14 hours = 14 * 60 = 840 minutes. It would take 840 minutes to groom 5 dogs and 3 cats. The answer is 840.

Q: Bill's take-home salary is $40,000. He pays $2,000 in property taxes, $3,000 in sales taxes, and 10% of his gross salary in income taxes. What is Bill's gross salary?
A: First, figure out how much Bill has before he pays property taxes: $40,000 + $2,000 = $42,000. Then, figure out how much Bill has before he pays sales taxes: $42,000 + $3,000 = $45,000. Next, figure out what percent of his salary Bill keeps after income tax: 100% - 10% = 90%. Now we know that .9g = $45,000, where g is Bill's gross salary. Now we can divide both sides of the equation by .9 to find that g = $50,000. The answer is 50000.

Q: The cost of Joe's new HVAC system is $20,000. It includes 2 conditioning zones, each with 5 vents. In dollars, what is the cost of the system per vent?
A:
Two zones with 5 vents per zone is 2 * 5 = 10 vents. Thus, the $20,000 system costs $20,000 / 10 = $2,000 per vent. The answer is 2000.