What is 0.8 as a rational number

0.8 as a rational number is 8/10 or simplified further as 4/5.

What is 0.8 repeated 8 as a rational number

0.8 repeated 8, denoted as 0.88888888, can be represented as a rational number by setting it equal to the fraction x.

To convert the repeating decimal to a fraction, we will multiply both sides of the equation by 10^8 (a 1 followed by 8 zeros) to eliminate the repeating part:

10^8 * x = 8.88888888...

Next, we subtract the original equation from the equation multiplied by 10^8:

(10^8 * x) - x = 8.88888888 - 0.88888888
10^8 * x - x = 8

Simplifying the equation:

(10^8 - 1) * x = 8

To isolate x, we divide both sides of the equation by (10^8 - 1):

x = 8 / (10^8 - 1)

Thus, 0.8 repeated 8 can be represented as the fraction 8 / (10^8 - 1) in rational form.

To express 0.8 as a rational number, we need to write it as a fraction in the form of a/b, where both a and b are integers and b is not equal to zero.

0.8 can be written as 8/10 because 0.8 is equivalent to the fraction where the decimal part is divided by 10.

However, we can simplify 8/10 by dividing both the numerator and denominator by their greatest common divisor.

The greatest common divisor of 8 and 10 is 2.

Dividing both 8 and 10 by 2, we get:

8 ÷ 2 = 4
10 ÷ 2 = 5

Therefore, 0.8 as a rational number is 4/5.