![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
The expression is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=4e7719d1ed7da91c5ebd0612bfdb6cfa.png\")
.
To add fractions the denominators must be equal.
\Find the least common denominator (LCD).
\Multiples of 4: 4,8,12,16,20,24,28,32.....
\Multiples of 7: 7,14,21,28,35......
\The least common multiple of 4 and 7 is 28.
\Rewrite each fraction with a common denominator of 28.
\![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=625dba9724922d404953dd55e5c3b9e1.png\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=19d6e9afcd3daa2b4697c0160c8b9138.png\")
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step2.JPG\")
Rewrite fractions using the LCD 28.
\![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=1def8c505c1ad1cd6de10ce18f27cbe1.png\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=241e1d0e889239f79b428faffe73cdb1.png\")
(Add: ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=eac4d2fa251b9dc9efa85506a9a9fa07.png\")
) \ \
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
The value of the expression is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=c1068a6551a0486ead09e016f4ca27e5.png\")
.