Solve.Mary and her brother John collect foreign coins. Mary has twice the number of coins that John has. Together they have 135 foreign coins. Find how many coins Mary has.
A. 18 coins
B. 45 coins
C. 90 coins
D. 81 coins
Answer: C
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Solve the problem.A projectile is fired from a height of 5.6 feet with an initial velocity of 163 ft/sec at an angle of 43° with the horizontal. The parametric equations for the path of the projectile are x = (163 cos 43°)t, and y = 5.6 + (163 sin 43°)t - 16t2,where x and y are in feet and t is in seconds. Find the height of the projectile after 4 seconds. Round your answer to the nearest tenth of a foot.
A. 386.3 ft B. 188.7 ft C. 476.8 ft D. 194.3 ft
Solve the problem.Add (6a4 - 7a2) and (5a4 - 2a2).
A. 2a6 B. 11a4 - 9a2 C. 2a12 D. 11a8 - 9a4
First round each number to one non-zero digit. Then perform the calculation using the rounded numbers to obtain an estimate.318.44 ÷ (41.9)
A. estimate: 7.5 B. estimate: 8.5 C. estimate: 7.6 D. estimate: 8
Solve the problem.If an investment of P dollars grows to A dollars in two years, the annual rate of return on the investment is given by 
Jared Spencer bought a collector's coin set for $770 and sold it two years later for $1192. What was the approximate annual rate of return of his investment? Round to the nearest tenth of a percent.
A. 19.4% B. 24.4% C. 27.4% D. 7.4%