zahra is anxious to save money on her utility bills and knows that changing the temperature of the water…

zahra is anxious to save money on her utility bills and knows that changing the temperature of the water when she does laundry can help save money. right now three - fourths of all her laundry is done with the hotter water. use the table below to determine how much she currently pays in utility costs for laundry. assume 1 load of wash per day.\n\n| clothes washer w/electric water heater | cost per load |\n| ---- | ---- |\n| hot wash & warm rinse | 71 cents per load |\n| warm wash & cold rinse | 25 cents per load |\n\nif she cuts down the amount of laundry that she does in hot water to one - half, about how much will she save every year?\n a. $65 each year\n b. $42 each year\n c. $23 each year\n d. $392 each year

zahra is anxious to save money on her utility bills and knows that changing the temperature of the water when she does laundry can help save money. right now three - fourths of all her laundry is done with the hotter water. use the table below to determine how much she currently pays in utility costs for laundry. assume 1 load of wash per day.\n\n| clothes washer w/electric water heater | cost per load |\n| ---- | ---- |\n| hot wash & warm rinse | 71 cents per load |\n| warm wash & cold rinse | 25 cents per load |\n\nif she cuts down the amount of laundry that she does in hot water to one - half, about how much will she save every year?\n a. $65 each year\n b. $42 each year\n c. $23 each year\n d. $392 each year

Answer

Explanation:

Step1: Calculate current annual cost for hot - wash laundry

There are 365 days in a year and 1 load per day. Currently, the fraction of hot - wash laundry is $\frac{3}{4}$. The cost per hot - wash load is 71 cents or $0.71$. The number of hot - wash loads per year is $365\times\frac{3}{4}=273.75$. The annual cost for hot - wash laundry is $273.75\times0.71 = 194.3625$ dollars. The number of warm - wash loads per year is $365\times(1 - \frac{3}{4})=365\times\frac{1}{4}=91.25$. The cost per warm - wash load is 25 cents or $0.25$. The annual cost for warm - wash laundry is $91.25\times0.25 = 22.8125$ dollars. The total current annual cost is $194.3625+22.8125 = 217.175$ dollars.

Step2: Calculate new annual cost after change

After the change, the fraction of hot - wash laundry is $\frac{1}{2}$. The number of hot - wash loads per year is $365\times\frac{1}{2}=182.5$. The annual cost for hot - wash laundry is $182.5\times0.71=129.575$ dollars. The number of warm - wash loads per year is $365\times(1 - \frac{1}{2}) = 182.5$. The annual cost for warm - wash laundry is $182.5\times0.25 = 45.625$ dollars. The new total annual cost is $129.575+45.625 = 175.2$ dollars.

Step3: Calculate the savings

The savings is the difference between the current total annual cost and the new total annual cost. Savings=$217.175 - 175.2=41.975\approx42$ dollars.

Answer:

B. $42 each year