In a 1200 m race, bike A beats bike B by 100 m. Bike B beats bike C by 100 m in a 600 m race. If bike A beats bike C by 30 sec in a 720 m race, then what is the speed of bike C?
In a 100 m race, A beats B by 20 m and B beats C by 20 m. By how much distance does A beat C.
(A) 64 m
(B) 24 m
(C) 25 m
(D) 36 m
Solution:
$${\text{A beat C by}} = \frac{{100}}{{25}} \times 9 = 36\,{\text{m}}$$
5.
In a 400 m race, A gives B a start of 5 seconds and beats him by 15 m. In another race of 400 m, A beats B by $$7\frac{1}{7}$$ seconds. Their respective speed are -
A's speed = 8 km/hr= $$\left( {8 \times \frac{5}{{18}}} \right)$$ m/sec = $$\frac{20}{9}$$ m/sec Time taken by A to cover 800 m = $$\left( {800 \times \frac{9}{{20}}} \right)$$ sec= 360 sec Time taken by B to cover 800 m = (360 + 15) sec = 375 sec ∴ Speed of B : = $$\frac{800}{375}$$ m/sec = $$\left( {\frac{{800}}{{375}} \times \frac{{18}}{5}} \right)$$ km/hr= $$\frac{192}{25}$$ km/hr= $$7\frac{17}{25}$$ km/hr
8.
In a 200 m race, A beats B by 35 m or 7 seconds. A's time over the course is-
(A) 40 sec
(B) 47 sec
(C) 33 sec
(D) None of these
Solution:
B covers 35 m in 7 seconds. B covers 200 m in = $$\left( {\frac{7}{{35}} \times 200} \right)$$ sec = 40 sec Time taken by A = (40 - 7) sec = 33 sec
9.
A gives B a head-start of 10 seconds in a 1500 m race and both finish the race at the same time. What is the time taken by A (in minutes) to finish the race if speed of B is 6 m/s?
(A) 3
(B) 4
(C) 8
(D) 5
Solution:
B's speed = 6 m/s B's distance in 10 second = 10 × 6 = 60 m \[\begin{array}{*{20}{c}} {}&{\text{A}}&{\text{B}} \\ {{\text{Distance}} \to }&{1500}&{1440} \\ {{\text{Speed}} \to }&x&6 \\ {{\text{Time}} \to }&{240{\text{ second}}}&{4\min } \end{array}\] ∵ Time same Time of B = Time of A Time of A = 4 min
10.
In a 1547 m race, Arjun reaches in 78 seconds, while Karan reaches the finish point in 91 seconds. By how much distance does Arjun beat Karan?
(A) 220 m
(B) 221 m
(C) 245 m
(D) 231 m
Solution:
Karan, 91 sec → 1547 m 1 sec → 17 m 78 sec → 1326 m Arjun, 78 sec → 1547 m Karan is defeated by Arjun by = 1547 - 1326 = 221 m