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An airline passenger is planing a trip that involves three connecting flights that leave from Airports A, B and C, respectively. The first flight leaves Airport A every hour, beginning at 8:00 a.m, and arrives at Airport B 2.5 hours later. The second flight leaves Airport B every 20 minutes, beginning at 8:00 a.m., and arrives at Airport C 1 1/6 hours later. The third flight leaves Airport C every hour, beginning at 8:45 a.m. What is the least total amount of time the passenger must spend between flights if all flights keep to their schedules ? A) 15 min B) 25 min C) 1 hr 5 min D) 1 hr 15 min E) 2 hr 20 min

A and B ran a race of 480 m. In the first heat, A gives B a head start of 48 m and beats him by 1/10 th of a minute. In the second heat, A gives B a head start of 144 m and is beaten by 1/30 th of a minute. What is B’s speed in m/s? (A) 12 (B) 14 © 16 (D) 18 (E) 20

Ax--------xB----------xD ````````````````````````````````| ````````````````````````````````| ````````````````````````````````| ````````````````````````````````| ````````````````````````````````xC we have AB = 5 and BC=10 side BD=CD = a sqrt(2a^2) = 100 => a = 10/sqrt(2) = 7.071 AC = sqrt((7.071+5)^2 + 7.071^2) = 14

3.14*r^2 = 63 => r = 4.48 3.14*(r+x)^2 = 18 + 63 = 81 => r + x = 5.08 x = 5.08 - 4.48 = 0.6 (ans. E)

I agree with oa : 0 - 13 and 17 are a primary numbers

One-third of a cement mixture that was 20 percent sand by weight was replaced by a second cement mixture of equal weight, resulting in a new mixture that was 25 percent sand by weight. The second cement mixture was what percent sand by weight ?

Yes, Thanks. It's very simply, but I raveled in statement "... that will remain in use for five years."

Each year, 1/6 of the old machines in a factory are replaced with new machines that will remain in use for five years. Approximately what percent of the old machines still remain after two years? A) 86% B) 77% C) 73% D) 71% E) 69%

Yes, the ansewer is E, I make equation: 3 + 10*n = 4 + 15 * m where m,n is 0, 1, 2, 3, ... and I have problem with analize - m, n must cover all week: 0 ...17 - I thing it is impossible to analyze by 2 min. I find more simpler solutions.

Buses leave town B at 3pm and every 10 hours after that. Buses leave town C at 4pm and every 15 hours after that. If the buses follow this schedule begining on Monday, what is the earliest day on wchich the buses leave at the same time ? A) Tuesday B) Wednesday C) Thursday D) Sunaday E) So long as they continue operating in this manner, they will never leave at the same time.

Xavier, Yvonne and Zelda each try independently to solve a problem. If their individual probabilities for success are 1/4, 1/2 and 5/8, respectively, what is the probability that Xavier and Yvonne, but not Zelda will solve the problem ? A)11/8 B)7/8 C)9/64 D)5/64 E)3/64

| 51 floor | ↓ 63 f/m, D1 - distance | x crash - For this point we describe equations | | | ↑ 57 f/m, D2 | 11 floor | Equations for point x: 63/D1=57/D2 => D1 = D2*63/57 D1 + D2 = 51 - 11 = 40 D2*63/57 + D2 = D2*120/57 = 40 => D2 = 19 Therefore they crash at 11+19 = 30TH floor

(1) A/X = N + 11 => A = N*X + 11 -------first number (2) B/X = M + 21 => B = M*X + 21 ------ second number X - divisor, N, M - integer A + B = N * X + M * X + 32 = (N + M)* X + 28 + 4 THEN X MUST BE 28

suppose x := -2 (x then: sqrt (-x*|x|) = sqrt (2*2) = 2 = -x

m is the quantity of milk x is the percentage of milk in the mixture A milkman sells the mixture at the same price ($3/liter) as before and makes a profit of 20%. we have: 1.2*3*m = 3(m + 5) => m=25 liter and milkman makes the mixture as: 5*x = m*(100-x) = 25*(100-x) => x= 83.33