When a certain number is multiplied by 7, the product entirely comprises ones only (1111....). What is the smallest such number?

A man completes 7/8 of a job in 21 days. How many more days will it take him to finish the job if quantum of work further increased by 50%?

Jay and Vijay spent an equal amount of money to buy some pens and special pencils of the same quality from the same store. If Jay bought 3 pens and 5 pencils, and Vijay bought 2 pens and 7 pencils, then which one of the following is correct?

P scored 40 marks more than Q in the examination. If Q scores 10% less marks than P, then how much did Q score?