Originally Posted by

**lexx** Okay so i've been working through some problems with upper and lower quartiles and have so far been understanding it until i came up against this question....

The Manager of Sam and Ellea's Restaurant looked at the receipts for the last two days. The following table shows the range of values.

**Amount of Receipt Frequency of Receipts ****Cumulative frequency**

0-0.99 17 17

1.00-1.99 85 102

2.00-2.99 140 242

3.00-3.99 75 317

4.00-4.99 82 399

5.00-5.99 73 472

6.00-6.99 62 534

7.00-7.99 21 555

8.00-8.99 14 569

9.00-9.99 22 591

10.00-15.00 43 634

then they ask to find the upper quartile or Q3.....

this is what i figured out for the upper quartile though i believe i am wrong but here it goes;

14, 17, 21, 22, 43, 62, 73, 75 82, 85, 140

q3 = 62 + 73 / 2

= 67.5

however i don't believe this is the right way to find the q3 when using a chart... Thanks for any help in advance!