MODE RANGE MEDIAN MEAN.

Introduction

MODE RANGE MEDIAN MEAN.

Task

Please copy and paste the link below into your search bar it has the definitions of Mode Median Range and Mean and practice problems.

http://www.purplemath.com/modules/meanmode.htm

Process

The weekly salaries of six employees at McDonalds are $140, $220, $90, $180, $140, $200.  For these six salaries, find: (a) the mean (b) the median (c) the mode

 

Andy has grades of 84, 65, and 76 on three math tests.  What grade must he obtain on the next test to have an average of exactly 80 for the four tests?

 

Test scores for a class of 20 students are as follows:
93, 84, 97, 98, 100, 78, 86, 100, 85, 92, 72, 55, 91, 90, 75, 94, 83, 60, 81, 95 

Test 
Scores

Frequency
91-100   
81-90   
71-80   
61-70  
51-60   

a) Find the modal interval.
    The "modal interval" is the interval containing the greatest frequency.  

b) Find the interval that contains the median.

 

 

Evaluation

 List the data in order: 90, 140, 140, 180, 200, 220

                                                                               
Mean:    90+ 140+ 140+ 180 + 200 + 220 = 
                                        6                             

Median:    90,140,140,180,200,220
The two numbers that fall in the middle need to be
averaged.     140 + 180 = 160
                           2 

Mode:   The number that appears the most is 140

 84 + 65 + 76+ x   =   80(average) cross multiply 
                   4                                         and solve

                        (4)(80) = 225 + x
                             320 = 225 + x
                           -225   -225

                               95 = x 

               Andy needs a 95 on his next test.

Test Scores  Frequency
91-100  9 
81-90  6
71-80 3
61-70 0 
51-60 2
  20  total
b. 91-100 is the modal interval. This interval has the most data.

c. The middle of 20 is 10. If I count from 
the top, 10 will fall in the interval 81-90.
If I count from the bottom and go up, 10 
will fall in the interval 81-90. The 
interval that contains the median is 
81 - 90.

 

Conclusion

Now you have learned MODE RANGE MEDIAN MEAN.