A contractor has got two orders A and B. On one (A) he spends Rs. 25,000 and makes a bill of Rs. 30,500. On the other (B) he makes a bill keeping a profit of 20%. Which of the two orders is more profitable to him?
A group of boys has an average weight of 36 kg. One boy weighing 42 kg leaves the group and another boy weighing 30 kg joins the group. If the average now becomes 35.7 kg, then how many boys are there in the group?
Keerthana takes 9 hrs 20 min in walking a distance and riding back to same place where she started. She could walk both ways in 11 hrs 15 min. The time taken by her to ride back both ways is