Define relative frequency.

What do you mean by class-frequency ? What is relative class-frequency of any class-interval?

Define relative refractive index. What is its relation with velocity of light?

Define relative lowering of vapour pressure.

Define relative error and percentage error in a measurement .

In a frequency distribution having 6 class intervals the total frequency is 100 and cumulative frequency less than type and cumulative frequency more than type corresponding to the fourth class interval are 86 and 50 respectively. Find the frequency of the fourth class interval.

For drawing a frequency polygon of a continuous frequency distribution, we plot the points whose ordinates are the frequencies of the respective classes and abscissae are the:

Calculate the relative equivalent weight of copper in cuprous oxide