Does 5/8 , 42.5/68 form a proportion?

yes

Step-by-step explanation:

cause 5/8 = .625 = 42.5/68

Explanation:

Two fractions A/B and C/D form a proportion when A/B = C/D.

In this case, we want to know if 5/8 = 42.5/68 is true or not.

Let's assume the two fractions are equal. We'll use the cross multiplication operation to get the following:

5/8 = 42.5/68

5*68 = 8*42.5

340 = 340

Both left and right hand sides evaluate to 340. That makes the last equation true, so the first equation must be true as well. Therefore, the two fractions do form a proportion.

Here's another example

Let's say we wanted to find out if 1/2 and 1/3 were equal or not. You can probably quickly tell that they are not equal. For now, assume they are equal and we'll show a contradiction happens

1/2 = 1/3 assume this is true

1*3 = 2*1 ... cross multiply

3 = 2 ... this is where the contradiction happens

We have a contradiction since the left and right sides don't match up. This contradiction has a domino effect to make the original equation false as well.

Let's go back to the original two fractions 5/8 and 42.5/68

We can use a calculator to convert each value to decimal form

5/8 = 0.625

42.5/68 = 0.625

Both result in the same decimal value 0.625, so that must mean the two fractions have to be equal and must be proportional.

This is an alternative method to the first section at the top of the page.

step-by-step explanation:

536

step-by-step explanation: