Question
A boat running downstream covers a distance of 42 km in
2 hrs while it covers the same distance upstream in 7 hrs. Then speed of the boat in still water isSolution
Let the speed of boat in still water be a km/hr and that of stream be b km/hr. Therefore, 42/(a + b)= 2 ⇒ a + b = 21 ………..(i) 42/(a – b)= 7 ⇒ a + b = 6 ………..(ii) On adding, eq (i) and (ii) ⇒ 2a = 27 km/hr ⇒ a = 13.5 km/hr
The ratio of the incomes of Vineet and Vidya is 15:8 respectively. Vineet saves 40% of his income while Vidya saves 25% of his income. The sum of their ...
- Find the fourth proportion of (k + 3), (2k - 6), and (4k - 9). (Note: 'k' is the smallest two-digit prime number.)
In the comparison between Colleges P and Q, the student ratio is 6:5, and in the relation between Colleges R and P, the ratio is 13:10. Additionally, th...
If the third proportion of 27 and 36 is β0.5kβ, then find the value of (k β 36) : (k + 12).
Some balls are to be distributed among some boys. If 4 more balls are available, each boy gets 6 balls. If 3 less balls are available, each boy gets 3 b...
βPβ, βQβ and βRβ hired a generator for a party. The owner charges a fixed rate per hour. If βPβ, βQβ and βRβ used it for 8 hour...
If 'R' is the prime number 3, then find the fourth proportion of (R + 2), (R - 1) and (R + 7).
βXβ, βYβ and βZβ divide a certain sum of money among themselves. The average of the amount with them is Rs. 2700. Share of βXβ is 12.5% ...
- Find the fourth proportion of (2k), (3k), and (4k + 8). (Note: 'k' is the smallest two-digit prime number.)
A, B and C entered into a partnership by investing in the ratio of 6:3:4. At the end of the year, the total profit is in the ratio of 12:3:8. Find the r...