Vivek is 30% more efficient than Neha. How much time will they, working together, take to complete a job which Vivek alone could have done in 23 days?

If the length of the diagonal of a square is $${ 10\sqrt{2}}$$ cm, then what will be the area of the square?

The arithmetic mean of the following data is .

23, 17,20,19,21

What is the sum of all three-digit numbers which are divisible by 20?

A person travels 600 km by train at 80 km/hr 800 km by ship at 400 km/ hr and 100 km by car at 50 km/hr. What is the average speed for the entire distance? 

The traffic lights at three different road crossings change after 24 seconds, 36 seconds and 54 seconds respectively. If they all change simultaneously at 10 : 15 : 00 AM, then at what time will they again change simultaneously? 

The average price of three furniture items is Rs 15,000. If the ratio of their prices is 3: 5: 7, then the cheapest furniture price is-

A car reaches its destination in time when moving with an average speed of 45 km/hr. But when it is moving at 30 km/hr, it is late by 10 minutes. Find the total distance of the journey?