Four years ago, the average age of a family of 9 members was 31 years. Two years later a man died at an age of 41 years, what is the present average age of the family? A) 32 B)33 C)34 D)35 E)36
I'm goin through the Kaplan book and now I'm on the Statistics chapter. My question is why the answer is B? I was so sure that the answer was D. Could anyone explain to me?
4. If x 4 and y 10, what is the range of the numbers in the set {5, 8, x, y}? (1) 3x + 5y = 72 (2) 7x + 7y = 56
Last year Harold's average time to finish the qualifying event was three hours. If he knows that he can increase his speed this year by 20%, how many minutes should it take him to complete the event?
The rearmost end of a 66 foot truck exits a 330 foot tunnel exactly 6 seconds after the frontmost end of the truck entered the tunnel. If the truck traveled the entire tunnel at a uniform speed, what is the speed of the truck in miles per hour (1 mile = 5,280 feet)?
In a horse race, the winning horse's nose crosses the finish line 6 seconds before that of the second place horse. If a horse measures 7 feet in length from nose to tail and the winning horse wins by 2 lengths, how fast is the losing horse traveling?
A. 6 feet per second B. 7/2 feet per second C. 3 feet per second D. 7/3 feet per second E. 7/6 feet per second
Two boys, Joe and Seth, can mow a lawn in 2 hours thirty minutes. If 3 other boys, Mike, Tommy and Teddy, helped, how long would it take to mow the same lawn with all of them starting at the same time?
(1) Joe mows faster than Seth. (2) Mike, Tommy, and Teddy would finish the same lawn in 1 hour 45 minutes.
Three hoses, x, y, and z, each pump water at a constant rate into a 70,000-gallon tank. How long will it take the hoses to fill the tank up to the 30,000-gallon mark?
(1) The 3 hoses working simultaneously can fill half the tank in 5 hours. (2) Hose y pumps water at half the rate of x.
Pam gets on an elevator at the 12th floor of a building going up. Hilary gets on an elevator on the 63rd floor at the same time in the same building going down. At what floor will their paths cross?
(1) Pam's elevator is moving at a rate of 4 floors per second. (2) Hilary's elevator is moving at a rate of 5 floor per second.