Anyone explains to me, Please.
1. On level farmland, two runners leave at the same time from the intersection of two country roads. One runner jogs due north at a constant rate of 8 miles per hour while the second runner jogs due east at a constant rate that is 4 miles per hour faster than the first runner's rate. How far apart, to the nearest mile, will they be after hour ?
(A) 6
(B) 7
(C) 8
(D) 12
(E) 14
Ans. B
2. The rear wheels of a car crossed a certain line 0.5 second after the front wheels crossed the same line. If the centers of the front and rear wheels are 20 feet apart and the car traveled in a straight line at a constant speed, which of the following gives the speed of the car in miles per hour? (5,280 feet = 1 mile)
(A) (20/5280)*{(60^2)/0.5}
(B) (20/5280)*{60/0.5}
(C) (20/5280)*{0.5/(60^2)}
(D) (20*5280)/{(60^2)*0.5}
(E) (20*5280)/{60*0.5}
Ans.A
1. On level farmland, two runners leave at the same time from the intersection of two country roads. One runner jogs due north at a constant rate of 8 miles per hour while the second runner jogs due east at a constant rate that is 4 miles per hour faster than the first runner's rate. How far apart, to the nearest mile, will they be after hour ?
(A) 6
(B) 7
(C) 8
(D) 12
(E) 14
Ans. B
2. The rear wheels of a car crossed a certain line 0.5 second after the front wheels crossed the same line. If the centers of the front and rear wheels are 20 feet apart and the car traveled in a straight line at a constant speed, which of the following gives the speed of the car in miles per hour? (5,280 feet = 1 mile)
(A) (20/5280)*{(60^2)/0.5}
(B) (20/5280)*{60/0.5}
(C) (20/5280)*{0.5/(60^2)}
(D) (20*5280)/{(60^2)*0.5}
(E) (20*5280)/{60*0.5}
Ans.A
:mrgreen:
