The mean and standard deviation of 100 items are 50, 5 and that of 150 items are 40, 6 respectively.   What is the combined standard deviation of all 250 items?

For election to the Lok Sabha, a nomination paper can be filed by

Miscellaneous · Easy

In a month if the seventh day is three days earlier than Saturday,then the nineteenth day of the month will be a

Miscellaneous · Easy

Which among the following events happened earliest ?

Miscellaneous · Easy

An 80-litre solution of alcohol and water has 75% alcohol. How much water (in litres) must be added to bring down the concentration of alcohol to 60%?

Miscellaneous · Easy