Question

classify each number below as an integer or not.
-30.79
91
\\(\frac{21}{7}\\)
\\(-\frac{19}{7}\\)
-564.15

Explanation:

Step1: Define integer criteria

Integers are whole numbers (positive, negative, zero) with no fractional/decimal part.

Step2: Evaluate -30.79

Has decimal part → Not integer.

Step3: Evaluate 91

Whole positive number → Integer.

Step4: Simplify $\frac{21}{7}$

$\frac{21}{7}=3$, whole number → Integer.

Step5: Simplify $-\frac{19}{7}$

$-\frac{19}{7}\approx-2.714$, has fractional part → Not integer.

Step6: Evaluate -564.15

Has decimal part → Not integer.

Answer:

• $-30.79$: No
• $91$: Yes
• $\frac{21}{7}$: Yes
• $-\frac{19}{7}$: No
• $-564.15$: No