Question 322918
The desks in a classroom are arranged in straight rows.
 John is in the third row from the front and the fourth row from the back.
 He is also third from the left end of a row and fifth from the right.
 How many desks are in the classroom?
:
No. of rows:
3 + 4 = 7 but John's row can only be counted once, rows = 6
No. of desk in a row. 3 + 5 = 8 but John's desk counted only once, desk = 7
Therefore:
6 * 7 = 42 desks in the classroom
:
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