Performing Operations in Public Health Contexts — Quiz Answers

An international plan to eliminate one virus is proposed. The time in years since the plan began, t , depending on the amount spent in billions of dollars, a , can be found using t=sqrt((a−5.7)/(−0.192)) How many months have passed if $⁢2.2 billion has been spent? Round the answer to the nearest whole number. Enter your answer in the box. [Blank 1] months

According to the Environmental Protection Agency (EPA), approximately 7 out of every 10 homes built between 1940 and 1959 have lead-based paint. The number of homes tested, t , depending on the number of positive results, p , can be estimated using the equation t=(p)/((7)/(10)) If 2,401 homes test positive, how many total homes were tested, according to the equation? Round the answer to the nearest whole number. Enter your answer in the box. [Blank 1] homes

The chronic daily intake of nitrates for 12 -year-old children who have an average body weight of 45 kg and drink 1 L of water per day can be found using the equation C⁢D⁢I=((I⁢R)⁢C)/(A⁢B⁢W) , where I⁢R is the intake rate in liters of water per day, C is the concentration of nitrate in milligrams per liters, and A⁢B⁢W is the average body weight. The rate is recalculated 18 months later for the same group of children, who are now drinking (1)/(4) L more per day and have a new average body weight of (1)/(2) kg more. In each test, there were 22.5 mg of nitrate in 2.5 L of water. Which expression represents the recalculation?

A program to clean up underground storage tanks operates at a deficit. The number of years since November 2015, t , depending on the net spending of the program in trillions of dollars, n , can be estimated using the formula t=sqrt((n+0.539)/(−0.015)) Complete the sentence describing the time when the net spending was −$⁢1.5 trillion. Move the correct answer to each box. Not all answers will be used. Put responses in the correct response input area to answer the question. Select a response, navigate to the desired input area and insert the response. Responses can be selected and inserted using the space bar, enter key, left mouse button or touchpad. Responses can also be moved by dragging with a mouse.

At most, Colorado saves $⁢187.2 million on dental costs by adding fluoride to the water. The state needs to add fluoride to the supply of 50 additional wastewater-treatment plants. The state estimates that it will save an additional $⁢34.4 million after adding fluoride to the supply of these plants. What is the percent change in savings if the current savings are (3)/(4) of $⁢187.2 million? Round the answer to the nearest whole number. Enter your answer in the box.

The cost per ton of cleaning up a spill, C , depending on the size of the spill, s , can be modeled using the equation C=12,318⁢sqrt(34−s)+9,758 , where s is the size of the spill in tons. If a new process promises to reduce the cost by (1)/(3) , what would the price per ton be if the spill involved 9 tons of oil? Round the answer to the nearest hundredth if necessary. Enter your answer in the box.

According to the Environmental Protection Agency (EPA), approximately 1 out of every 4 homes built between 1960 and 1979 has lead-based paint, as do 7 out of every 10 homes built between 1940 and 1959 The total number of homes tested, t , depending on the number of positive results of homes built between 1960 and 1979 , x , and the number of positive results of homes built between 1940 and 1959 , y , can be estimated using the equation t=(x)/((1)/(4))+(y)/((7)/(10)) If 392 homes built between 1960 and 1979 test positive, and 148 homes built between 1940 and 1959 test positive, then how many total homes were tested, according to the equation? Round the answer to the nearest whole number. Enter your answer in the box. [Blank 1] homes