Monday

December 22, 2014

December 22, 2014

Posted by **Sam** on Tuesday, February 13, 2007 at 9:01pm.

The photocopying machine in a school office is made available to teachers between the hours of 3pm and 4pm. Mr. Grim and Mrs. Grump each have 10 minutes of copying to do each day. If theyh each enter the office at points in the available hour, what is the probability that one of them will have to wait while the other finishes copying?

Hi Sam. Welcome to Jiskha!

Draw yourself an x,y plot with both axes running from 0 to 50 minutes, representing the times that Grim (x) and Grump (y) might enter the room, measured from 3 PM. Assume those times are randomly distributed. The area of (x,y) space where |x-y| < 10 is the region where one or the other person is going to have to wait.

The probability that one of them will have to wait is the ratio or the area of a diagonal region between the lines x = y + 10 and x = y - 10, to the area of the 50 x 50 square. I get that ratio to be

1 - (2*0.5*40*40)/(50*50) = 1 - 16/25 = 9/25

The number (2*0.5*40*40)/(50*50) = 16/25 is the fraction of x,y space where no waiting is required, and is the ratio of the sum or two right-triangular areas to that of the 50 x 50 square

**Answer this Question**

**Related Questions**

linear programming app - write the constraints as linear inequalities and ...

Algebra 2 (Linear Programming) - Part A requires 4 hours per unit on a lathe and...

Algebra 1A - How many solution sets do systems of linear inequalities have? Do ...

math - How many solution sets do systems of linear inequalities have? Do ...

Algebra 1 - How many solution sets do systems of linear inequalities have? Do ...

linear programming app - solve this linear programming problem; A chain saw ...

linear programming - A manufacturer produces two items, bookcases and library ...

Pre-Calculus check answers - Describe the linear programming situation for this ...

Pre-Calculus-check answers - Describe the linear programming situation for this ...

Pre-calculus-check answers - Describe the linear programming situation for this ...