Is the 0.5,5 cyclic decimal a rational number How to prove that 0.5,5 cycles are rational

Is the 0.5,5 cyclic decimal a rational number How to prove that 0.5,5 cycles are rational

Infinite non-circulating decimals and numbers with open roots are called irrational numbers, such as pi,3.141592653...
And rational numbers and it is the opposite, integers and fractions are collectively called rational numbers
Includes integers and commonly called fractions, which can also be expressed as finite or infinite cyclic decimals.
Rational number can be expressed in the form of a/b, where a, b are integers, and mutual quality. We often use rational number. For example, how much money, how many pounds.
Any real number which can not be expressed in the form of a/b is an irrational number, also called infinite noncirculating decimal.
0.55555...=5/9, So it is a rational number.
In fact, there is no need to prove, because the definition of rational number is very clear, so according to the definition can be directly proved.

If the difference between two numbers is negative, then the two numbers must be () A. The minus is positive and the minus is negative B. The minus is negative and the minus is positive C. The minus is negative and the minus is negative D. Less subtracted than subtracted

If the difference between two numbers is negative, the two numbers must be subtracted less than the subtracted number.
Therefore, D.

If the difference between two numbers is negative, then the two numbers must be less subtracted than subtracted.
Therefore, D.