A business woman has $300,000 of profits from her office supply company invested in two
investments. One has a yearly return of 6% and the other has a yearly return of 7%. If the
total yearly income from the investments is $19,300, how much is invested at each rate?
A botanist collected data from an experiment on the amount of oxygen released by a plant
given different amounts of an experimental fertilizer. He graphs the data with grams of
fertilizer given in a day on the x–axis and milliliters of oxygen produced in a day on the
y–axis. His data points are: (1, 0.02), (3, 0.02), (5, 0.02),
(7, 0.02). Find an equation for the line which fits this data and interpret its meaning.
In a test of a diet for pigs, the average live weight w (in kilograms) of a pig was a linear
function of the number d of days after the start of the diet, where 0 d
50. The weight of a
pig at the beginning of a diet was 25 kg and thereafter the pig gained 5 kg every nine days.
(a) Express w as a function of d. (b) Find the weight of a pig 36 days after the beginning of
the diet.
Find the x–intercept made by the line that passes through the points (1, –1) and (–1, 0).
A baby weighs 9 pounds at birth and 30 pounds at age 3. Use a graphing calculator to
graph the resulting equation and determine how much the child will weight at age 12.
A chemist has two solutions that contain different concentrations of hydrochloric acid. One
is a 20% concentration and the other is a 12% concentration. How many cubic centimeters
of each should he mix to obtain 100 cc with a concentration of 15.2%?