Question
Boat ‘A’ can cover 250 km in still water in 10
hours. In still water, if the ratio of the speed of boat ‘A’ to that of ‘B’ is 5:4 and the speed of stream is 5 km/hr then find the time taken by boat ‘B’ to cover the 275 km in downstream.Solution
Speed of boat ‘A’ in still water = 250/10 = 25 km/hr Speed of boat ‘B’ in still water = 25 × (4/5) = 20 km/hr Downstream speed of boat ‘B’ = 20 + 5 = 25 km/hr Time taken by boat ‘B’ to cover 275 km in downstream = 275/25 = 11 hours
The average marks scored by 20 boys and 45 girls are 88 and 94 respectively. Find the average marks scored by all the students together. (Answer should ...
The average of six numbers is 8. When three new numbers are included in such a way that the first number is twice the second and second number is thri...
5 positive numbers are written on a piece of paper. Sum of first 3 numbers is 70 and ratio of the 4th and the 5th number is 2:3. If difference between t...
A toy seller has white, pink, and blue balls in the ratio 3:7:11. The number of pink balls is more than the number of white balls by a number which is a...
A frustum of a cone has radii of 5 cm and 3 cm, and a height of 8 cm. What is its volume?
A and B started a business investing Rs. 1500 for ‘x’ months and Rs. 1800 for 10 months, respectively. Out of total profit of Rs. 5000, profit shar...
In a group of 3 numbers, the 1st is double of 2nd and half of third. If the average of the three numbers is 56 then find the difference between t...
The average age of a group of 8 friends is 30 years. If one of them leaves, the average becomes 29. Find the age of the friend who left.
- The number of students in class 'A' is 144, and the ratio of the number of girls to boys in class 'A' is 5:7. If the average number of boys in classes 'A' ...
Relevant for Exams:
