# What is the GCF of 18 and 30?

##### 1 Answer

Mar 8, 2018

#### Explanation:

#"this method uses only "color(blue)"subtraction"" to find GCF"#

#• " Subtract smaller number from larger number"#

#• " Repeat this until a "color(red)"common value ""is obtained"#

#• "The "color(red)"common value ""is the GCF"#

#•color(white)(x)30" and "18larrcolor(blue)"starting numbers"#

#30-18=12larr"larger subtract smaller"#

#•color(white)(x)18" and "12larrcolor(blue)"numbers after subtraction"#

#18-12=6larr"larger subtract smaller"#

#•color(white)(x)12" and "6larrcolor(blue)"numbers after subtraction"#

#12-6=6larr"larger subtract smaller"#

#•color(white)(x)6" and "6larrcolor(red)"common value"#

#rArr"GCF "=6#