Mahesh bought 50 kg of wheat at Rs.8 per kg and 150 kg at the rate of Rs. 7 per kg. He sold the mixture to get 12% profit. At what price per kg did he sell the mixture?

1)  Rs. 7.37

2)  Rs  7.84

3)  Rs. 8.40

(4) None of these

Two trains start, from Delhi and Chandigarh and move towards each other at speeds 80 km/hrand 90 km/hr respectively. At their meeting point it is found that the train from Chandigarh has traveled 40 km more than the train coming from Delhi. Find, the distance between Delhi and Chandigarh.

1) 620 km

2) 680 km

3) 720 km

4) 800 km