Question

Katrina drinks 0.5 gallons of water per day. Which expression shows how to find the number of cups of water she drinks in a week? There are 16 cups in a gallon. StartFraction 0.5 gallons Over 1 day EndFraction × StartFraction 16 cups Over 1 gallon EndFraction × StartFraction 1 week Over 7 days EndFraction StartFraction 0.5 gallons Over 1 day EndFraction × StartFraction 1 gallon Over 16 cups EndFraction × StartFraction 7 days Over 1 week EndFraction StartFraction 0.5 gallons Over 1 day EndFraction × StartFraction 1 gallon Over 16 cups EndFraction × StartFraction 1 week Over 7 days EndFraction StartFraction 0.5 gallons Over 1 day EndFraction × StartFraction 16 cups Over 1 gallon EndFraction × StartFraction 7 days Over 1 week EndFraction

Answer 1

Answer:option D.) 0.5 gallons / 1 day × 16 cups / 1 gallon × 7 days / 1 week

Step-by-step explanation:

The answer is found by doing analyzing the dimensions (units) of the quantities, placing each factor in a way that leads to the cancellation of the  dimensions (units) until you reach the desired units.You want to find an amount whose final (desired) units are  number of cups of water per week.Therefore, you have to change the given volume of water, that is in gallons, to cups, and the given unit of time, that is in days, to weeks.To do that, you use the conversion factors derived from the equivalences of the units:16 cups = 1 gallon  division property ⇒ 1 = 16 cups / gallon

1 week = 7 days

      division property ⇒ 1 = 7 days / weekThe final step is multiply the given amount,  0.5 gallons of water per day, by the conversion factors that wre just built:  0.5 gallon / 1 day = 0.5 gallon / (1 day) × 16 (cups / gallon) × (7 days / week)

Answer 2

D is the answer. hope this helps