6th grade fractions multiplied by a whole number

G

Guest

Guest
we forgot how to multiply mixed number by a whole number. I just need to see acouple of lines of how to work the problem and I'll remember
 
Two choices
15*(1+2/3) = 15*1+15*2/3 = 15+10 or
15*(1+2/3) = 15*5/3 = 75/3

11*(5+1/2) = 11*5 + 11/2 = 55 +5+1/2 or
11*11/2 = 121/2 = 60 + 1/2
 
There are two ways to look at this.

1) Change the mixed number to an improper fraction and then multiply.

e.g., multiply 8 1/3 by 6

Change 8 1/3 to an improper by multiplying 3*8 and adding this result to the numerator, 1. Write this over the denominator, 3. You get:

25/3

Multiply this by 6 to get:

6*25/3 = 50

2) Rewrite 8 1/3 as 8 + 1/3. Multiply this by 6 using the Distributive Law:

6(8 + 1/3) = 6*8 + 6* 1/3 = 48 + 2 = 50

Hope that helps...

Steve
 
Hello, bobbys!

I think Gene's second method is the easiest.


Example: \(\displaystyle \L\,2\frac{1}{3}\,\times\,4\)

Change both numbers into fractions: \(\displaystyle \L\,\frac{7}{3}\,\times\,\frac{4}{1}\)

Multiply: \(\displaystyle \L\,\frac{28}{3}\)

Convert to a mixed number: \(\displaystyle \L\,9\frac{1}{3}\)
 
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