Arithmetic mean of 10 observations is 60 and sum of squares of deviations from 50 is 5000. What is the standard deviation of the observations?
20
21
22.36
24.70
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