Calculate the perimeter of a parallelogram with sides 6 3/4 inches and 5 1/2 inches?

2 Answers
Dec 25, 2015

2412 in

Explanation:

Parallelograms have opposite and congruent sides.

This means that the 4 sides of the parallelogram are

634,634,512,512

To find the perimeter, add these all together.

First convert the mixed fractions into improper fractions.

634=274

512=112

Now, when we add these, we should have a common denominator between

274 and 112

112=224

Now, add the 4 sides:

274+274+224+224=984

492=2412 in

May 2, 2016

This one is an exercise in fractions which can be done mentally, rather than by the pure application of a method. The fact that the perimeter is asked for is citing the reason to add fractions.

Explanation:

P = 634+512+634+512

Work with the whole numbers first, giving: 6+5+6+5 = 22

Now add the fractions: 12+12=1 and 34+34=112

So, the perimeter = 22+1+112=2412

But, let's look at 34+34=112 again.

34=12+14

In 34+34 we have 12+14+34

The two fractions in red add to make 1, then the 12 can be added giving 112

Try to work questions like this in your head first, then you can check on paper, or as a last resort, with a calculator.