Question
A race track is in the shape of a rectangle with length
of 13 metres and area of 1300 m2. A car takes 10 seconds to make one lap around the perimeter of this track. If the car and a person whose speed is 5 m/s, started moving at the same time along the perimeter of the track but in opposite directions, then find the distance between the car and the person, 3 seconds before they cross each other.Solution
Area of the track = length of track x breadth of track = 13 x breadth of track = 1300 So, breadth of track = 1300 ÷ 13 = 100 So, perimeter of the track = (13 + 100) x 2 = 226 metres So, speed of the car = (226/10) = 22.6 m/s Relative speed of the car with respect to the person = 22.6 + 5 = 27.6 m/s So, distance between the car and the person, 3 seconds before they cross each other = 27.6 x 3 = 82.8 metres
Present age of P is 25% more than that of Q. Present age of R, who is 8 years older than Q, is 28 years. After how many years from now, ratio of ages of...
A boy’s age is 125% of what it was 8 years ago, but 75% of what it will be after 8 years. What is his present age?
When 18 years is subtracted from the present age of A and the obtained result is divided by 3, then the present age of his nephew is obtained. If the pr...
Five years ago from now, ratio of ages of Neha and Reema was 3:7, respectively. If 5 years hence from now, ratio of their ages will be 5:9, then find th...
12 years ago, the ratio of the ages of Ivan and Jenny was 2:1. The present age of Carl is 18 years more than one-sixth of Jenny’s present age. Find th...
5 years ago, the average age of a family of five persons was 30 years. In between these 5 years the family adopted a girl. Now at present the average ag...
- The sum of present ages of Rina and Tina is 72 years. After 6 years, the ratio of their ages will be 5:7. Find the difference in their ages.
Five years ago, the average age of a family of four members was 25 years. Six years hence, the ratio of their ages will be 9:7:5:3. Find the a...
The ages of A, B and C together are 60 years. B is thrice as old as A and C is 5 years older than A. What is the difference between ages of B and C?
- The current age ratio of 'P' and 'Q' is 4:7 respectively. The ratio of the age of 'P' six years from now and the age of 'Q' six years ago is 5:6 respective...
