Which of the following numbers is an integer?

Which of the following numbers is an integer?

• A. -3
• B. 1/2
• C. 0.5
• D. sqrt(2)

Answer: (A)

An integer is a whole number with no fractional part, and it can be negative, zero, or positive. Among the given numbers, the one that fits this is the negative three, since it is a whole number with no fractional component. The others don’t fit: one-half equals 0.5, which has a fractional part; 0.5 is just another way to write the same non-integer; and the square root of 2 is irrational, not a whole number. So the only integer here is -3.

An integer is a whole number with no fractional part, and it can be negative, zero, or positive. Among the given numbers, the one that fits this is the negative three, since it is a whole number with no fractional component. The others don’t fit: one-half equals 0.5, which has a fractional part; 0.5 is just another way to write the same non-integer; and the square root of 2 is irrational, not a whole number. So the only integer here is -3.