The marks (out of 100) obtained by a group of students in a General Knowledge. Class 7

The marks (out of 100) obtained by a group of students in a General Knowledge. Class 7

Question 1.

The marks (out of 100) obtained by a group of students in a General Knowledge quiz are 85, 76, 90, 85, 39, 48, 56, 95, 81 and 75. Another group’s scores in the same quiz are 68, 59, 73, 86, 47, 79, 90, 93 and 86. Compare and describe both the groups performance using, mean and median. Class 7

Solution:

Mean of the first group = [latex]\frac {85+76+90+85+39+48+56+95+81+75}{10}[/latex]

= [latex]\frac {72}{10}[/latex] = 72

Median of the first group : 39, 48, 56, 75, 76, 81, 85, 85, 90, 95 (Ascending order)

Median = [latex]\frac {76+81}{2}[/latex] = [latex]\frac {157}{2}[/latex] = 78.5

Mean of the second group = [latex]\frac {47+59+68+73+79+86+86+90+93}{10}[/latex]

= [latex]\frac {681}{9}[/latex] = [latex]\frac {227}{3}[/latex] = 75[latex]\frac {2}{3}[/latex]

Median of the second group : (9 + 1)th = 5th term = 79.

Question 2.

Consider this data collected from a survey of a colony. Class 7

Choose an appropriate scale and draw a double-bar graph. Write down your observations.

Solution:

Do as directed. Use scale as 1 unit = 100 persons.