Posted by **Khelany** on Friday, September 6, 2013 at 11:31pm.

A rectangular rice land is to be fenced along 4 sides and in the middle to divide it into to 2 equal areas. If 200m of fencing is available, what is the maximum area to be fenced?

- Math -
**Graham**, Friday, September 6, 2013 at 11:50pm
Assume that length l is greater than or equal to width w. Assert that the dividing fencing must be equal to the width (ie it must be perpendicular) by reasoning that if it were at any other angle, it would be longer, and the length would be reduced.

A = w * l

200 = 3w + 2l

.: A = w*(200-3w)/2

or A = 100 w - (3/2) w^2

Take the derivative and find when this is 0.

0 = (d/dw) (100 w-(3/2)w^2)

Solve for w, use to determine A

- Math -
**Anonymous**, Sunday, September 8, 2013 at 10:11am
where did you get the 3w

- Math -
**Graham**, Tuesday, October 1, 2013 at 3:21am
The 200m fencing is used for two length-sides (l), two width-sides (w) and the middle divider (w).

This: 200 = 2l + 3w

## Answer this Question

## Related Questions

- math - a rectangular garden is to be fenced along four sides and in the middle ...
- algebra - A rancher has 4 comma 7004,700 feet of fencing available to enclose a ...
- College Algebra - The campus of a college has plans to construct a rectangular ...
- Algebra - A community college campus plans to construct a rectangular parking ...
- Math - A rectangular garden is to be fenced off and divided into 3 equal ...
- pre- calc - area of a parking lot: One campus of Houston community college has ...
- Math - A rectangular field will be fenced on all four sides. Fencing for the ...
- geometry - a field bounded on one side by a river is to be fenced on three sides...
- Precalculus - A farmer has 1000 feet of fencing materials available to fence a ...
- math - You have two formulas to use: A = lw -->area = length times width P = ...

More Related Questions