A, B and C can complete a certain work in 30 days. B and C together can complete the same work in 45 days. If B is 20% more efficient than A, then B alone can complete one-third of the same work in:
Shyam drives his car 30 km at a speed of 45 km/h and, for the next 1 h 20 m, he drives it at a speed of 51 km/h. Find his average speed (in km/h) for the entire journey.
A marks her goods 25% above the cost price. She sells 25% of the goods at the marked price, 60% at 25% discount and the remaining at 10% discount. What is her overall gain or loss percent?