Difference between revisions of "1997 PMWC Problems/Problem I11"
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| − | + | ==Problem== | |
| + | A rectangle ABCD is made up of five small congruent rectangles as shown in the given figure. Find the perimeter, in cm, of ABCD if its area is <math>6750 cm^2</math>. | ||
| + | [[Image:ABCD.gif]] | ||
| + | |||
| + | ==Solution== | ||
| + | |||
| + | Let l and w be the length, and width, respectively, of one of the little rectangles. | ||
| + | |||
| + | <math>3w=2l</math> | ||
| + | |||
| + | <math>l=\dfrac{3}{2}w</math> | ||
| + | |||
| + | <math>6750=\dfrac{15}{2}w^2</math> | ||
| + | |||
| + | <math>w=30</math> | ||
| + | |||
| + | The perimeter of the big rectangle is | ||
| + | |||
| + | <math>2(w+l)+3w=330</math> | ||
Revision as of 18:38, 8 October 2007
Problem
A rectangle ABCD is made up of five small congruent rectangles as shown in the given figure. Find the perimeter, in cm, of ABCD if its area is 
.
Solution
Let l and w be the length, and width, respectively, of one of the little rectangles.
The perimeter of the big rectangle is
