document.write( "Question 660854: Three penguins, Pesky, Waddles and Tux all went to the Antarctic Amusement Park. The new ride, called the Crevasse, looked very exciting. Unfortunately, there was a weight limit of 110 kg for the ride. All three wanted to ride together but weren’t sure if it was safe. Since the scale can only hold 2 penguins at a time, it was very hard for them to figure out the weight of all 3 together. (Being social birds, they didn’t want to get on the scale alone.) Here is what they found:
\n" ); document.write( " Pesky and Waddles weighed 80 kg
\n" ); document.write( " Pesky and Tux weighed 56 kg
\n" ); document.write( " Waddles and Tux weighed 90 kg.\r
\n" ); document.write( "\n" ); document.write( "Can they all ride the Crevasse together? \n" ); document.write( "
Algebra.Com's Answer #412889 by kevwill(135)\"\" \"About 
You can put this solution on YOUR website!
There are several ways to solve this problem (e.g. as a system of linear equations or by substitution). However, since we're not looking for each penguin's individual weight, there is a simple way to do it.
\n" ); document.write( "Let p by Pesky's weight, w be Waddle's weight, and t be Tux's weight. Here's what we're given:
\n" ); document.write( "\"p+%2B+w+=+80\"
\n" ); document.write( "\"p+%2B+t+=+56\"
\n" ); document.write( "\"w+%2B+t+=+90\"
\n" ); document.write( "Add all three equations together:
\n" ); document.write( "\"p+%2B+w+%2B+p+%2B+t+%2B+w+%2B+t+=+80+%2B+56+%2B+90\"
\n" ); document.write( "\"2p+%2B+2w+%2B+2t+=+226\"
\n" ); document.write( "\"2%28p+%2B+w+%2B+t%29+=+226\"
\n" ); document.write( "\"%282%28p+%2B+w+%2B+t%29%29%2F2+=+226%2F2\"
\n" ); document.write( "\"p+%2B+w+%2B+t+=+113\"
\n" ); document.write( "So the combined weight of all three penguins is 113 kg. Unfortunately, they can't all ride the Crevasse together.
\n" ); document.write( " \n" ); document.write( "
\n" );