Jill walked 8 1/8 miles to a park and then 7 2/5 miles home. How many miles did she walk in all?

3 Answers
Feb 24, 2018

Okay, I think the easiest way to approach this problem is to first convert the mixed fractions to irregular fractions:

8 1/8=(8*8+1)/8=65/8

7 2/5=(7*5+2)/5=37/5

We want the total number of miles, so our equation is:

distance=65/8+37/5

The LCD of 5 and 8 is 5*8=40, so:

distance=325/40+296/40

distance=621/40=15 21/40 miles.

Hope this helps!

Feb 24, 2018

She walked 15 21/40 miles in all.

Explanation:

Jill walked 8 1/8 miles to a park i.e. 8+1/8 miles

and then 7 2/5 miles home i.e. 7+2/5 miles

In all she walked 8+1/8+7+2/5 miles

or 8+7+1/8+2/5 miles

or 15+(1xx5)/(8xx5)+(2xx8)/(5xx8) miles

or 15+5/40+16/40 miles

or 15+(5+16)/40 miles

or 15+21/40 miles

i.e. 15 21/40 miles

15 21/40

Explanation:

We can do this a couple of ways.

Improper fractions

8 1/8 + 7 2/5

Make improper fractions by multiplying the whole number by the denominator, then add the numerator (so for instance with the first mixed number, we'll have (8xx8+1)/8=65/8

65/8+37/5

Now we need to have the denominators be the same:

65/8(5/5)+37/5(8/8)=325/40+296/40

621/40

And now we divide it back out:

15.525=15 21/40

~~~~~

We can avoid the large numbers by adding the whole numbers first, then adding the fractions:

8 1/8 + 7 2/5=8+1/8+7+2/5=8+7+1/8+2/5=15+1/8+2/5

And now we add the fractions by finding a common denominator:

15+(1/8)(5/5)+(2/5)(8/8)

15+5/40+16/40=15+21/40=15 21/40