How do you subtract #-1\frac { 9} { 10} - 4\frac { 2} { 5}#?

1 Answer
Jul 21, 2017

See a solution process below:

Explanation:

To subtract these two numbers we first need to convert the mixed numbers into improper fractions:

#-1 9/10 - 4 2/5 => -(1 + 9/10) - (4 + 2/5) =>#

#-([10/10 xx 1] + 9/10) - ([5/5 xx 4] + 2/5) =>#

#-(10/10 + 9/10) - (20/5 + 2/5) =>#

#-19/10 - 22/5#

Next, we need each fraction over a common denominator. We will multiply the fraction on the right by the appropriate form of #1#:

#-19/10 - (2/2 xx 22/5) =>#

#-19/10 - 44/10#

Then, we can subtract the numerators over the common denominator:

#-19/10 - 44/10 => (-19 - 44)/10 =>#

#-63/10#

Now, if necessary, we can convert the improper fraction into a mixed number:

#-63/10 => -(60 + 3)/10 => -(60/10 + 3/10) => -(6 + 3/10) =>#

#-6 3/10#