Math Fractions & Equations : Cross Multiplying Proportions

The best way to multiply proportions is through cross multiplication. Reduce a proportion before cross multiplying with help from a math author and teacher in this free video on math lessons.

Expert: Brian Leaf
Bio: Brian Leaf, MA, is the author of McGraw-Hill's Top 50 Skills for SAT/ACT Success series and has instructed SAT, ACT, GED and SSAT preparation to thousands of students.
Filmmaker: David Pakman

[itsAdore]

My teacher made it sound hard but he makes it sound easy :D

[mountaindewed]

lol, you're funny! I can't understand why you still get hate for such an old comment. I guess these math nerds don't have a good sense of humor.

[jsoncoding]

i know HOW to do it but can someone explain the logic of why this works

[rustypasta]

@mario64shine That has to be the corniest comment I have ever read.
:/