0.2 also equals 5?

[LedLoaf]

In the “Rate Of Change” example, 8.9 / 0.2 = 44, the instructor states that 0.2 is also 5, so you can multiple 8.9 by 5. How did he find out that 0.2 equals 5?

[Chiko]

Hey @LedLoaf,

dividing it by 0.2 is the same as multiplying by (1 / 0.2)

1 / 0.2 = 5

[garypettie]

When you divide by a fraction, you can get the same result from multiplying by something known as the reciprocal.
You can really just think of the reciprocal as the number flipped on its head.

So, if you have 1/5 (which is 0.2 as a fraction), the reciprocal is 5/1 or just 5.

This means that;
8.9 / (1/5) = 8.9 * 5 = 44.5

I hope that helps.

[LedLoaf]

Yes, thanks, messing around with the calculator portion I discovered that about the reciprocal. Much appreciated.