mean in grouped formula

There are three methods to find mean for a frequency distribution. (i) Direct method: where x is the mid-interval f is the frequency M is the mean (ii) Short-cut method: where A = assumed mean d = x - A (iii) Step-deviation method: where i = class size We illu..

Ionic radii increases down a group. Na + < K + < Rb + < Cs + F - < Cl - < Br - < I - This is because the number of shells increase. screening effect increases..

Discovery - Daniel Rutherford, a Scottish Physician, discovered nitrogen in 1772. But it was Lavoisier, who proved that nitrogen is an element and that it was not a supporter of combustion and respiration. He called it 'azote' meaning 'no life'. The name 'Nitrogen' was given to it by Jean..

The readings of diastolic blood pressure of a group of volunteers for a medical experiment were normally distributed with a mean of 82 and a standard deviation of 8. If volunteers are to be selected from the middle 50% group, then find the upper and the lower readings,..

The means of each group of a two-way analysis of variance for two independent variables are plotted as shown in the graph. What does the graph represent about the interaction of the variables? => Disordinal interaction or Ordinal interaction or No interaction..

The means of each group of a two-way analysis of variance for two independent variables are plotted and shown in the three graphs. Which of these represents an ordinal interaction? Consider the interaction to be significant. => Graph 2 or Both graph 1 and graph 2 or Graph 3 or G..

Mean is the arithmetic avera..

Pollution can be anything - which damages the ecosystem and destroys the delicate balance in the ecosystem. Thereby, it creates health hazards to human beings and animals besides damaging the ecosystem. For e.g., industries polluting air has set imbalance in composition of air and made it unworthy ..

Separation of petroleum into simpler fractions after the removal of unwanted material..

Group 17 of the periodic table contains the elements fluorine, chlorine, bromine, iodine and astatine. These elements are collectively known as the HALOGENS. This name is derived from two Greek words Halo and Gens meaning 'salt producing'. Halogens are among the most reactive no..