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 Question from negra, a student: an average-sized person can burn about 6 1/2 calories a minute while riding a bike. Which of the following is equivalent to that amount? a) 1 2/2 b) 5 6/2 c) 6 2/4 d)6 2/6

We have two responses for you

Hi Negra.

Each of the choices is an integer plus a fraction. Express each of the fractions in lowest terms to see if one of them is equivalent to six and one half.

Penny

Hi Negra.

To compare the quantities, it would help to convert them to improper
fractions with the same denominator.

For example, if I wanted to know whether 3 20/3 is the same as 8 5/9,
I would first convert these to improper fractions:

3 20/3 = 3 + 20/3 = 3x(3/3) + 20/3 = 9/3 + 20/3 = (9 + 20) / 3 = 29 / 3.

and

8 5/9 = 8 + 5/9 = 8(9/9) + 5/9 = 72/9 + 5/9 = (72 + 5) / 9 = 77 / 9.

Now I try to find a common denominator for 29 / 3 and 77 / 9. I think
9 works, so
(29 / 3) x (3 / 3) = (29 x 3) / (3 x 3) = 87 / 9.

So I have shown that 3 20/3 is the same as 87/9 and 8 5/9 is the same
as 77/9. So I know that 3 20/3 is larger than 8 5/9.

You can compare your mixed fractions the same way.

Cheers,
Stephen La Rocque.

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