You will need to know integer rules for both positive and negative integers for your math test.
Integers are positive and negative whole numbers.
Accordingly, integers do not contain fractions or decimals.
You will need to solve basic equations that contain positive and negative integers on most exams.
If you have to take an advanced math examination, you will also need to understand integer rules for positive and negative integers in order to solve algebra and college-level math problems.
Integer Rules − Positive Integers
(1) Simplify the following mathematical expression: 205 + 56 – 38 = ?
A. 111
B. 213
C. 223
D. 299
E. –223
Tip: For simplicity, you might want to do the addition before performing the subtraction.
STEP 1: Deal with adding the positive numbers.
205 + 56 – 38 =
(205 + 56) – 38 =
261 − 38
STEP 2: Do the subtraction in order to solve the problem.
261 − 38 = 223
So, the correct answer is C.
Integer Rules − Negative Integers
(2) Simplify the following mathematical expression: –304 − (–17) + (−20) = ?
A. –301
B. –303
C. –307
D. –324
E. –341
Be careful with negative signs when answering questions like this one.
Remember that two negative signs together make a positive.
In other words, when you are asked to subtract a negative number, you actually have to add that number back in.
So, your first step should be to sort out the negative signs.
STEP 1: Deal with the subtraction of the negative number.
–304 − (–17) + (−20) =
–304 + 17 + (−20)
STEP 2: Deal with the addition of the negative number.
–304 + 17 + (−20) =
–304 + 17 − 20
STEP 3: Place the negative numbers together and simplify for the negative integers.
–304 + 17 − 20 =
–304 − 20 + 17 =
–324 + 17
STEP 4: Add in the positive number by reducing it from the negative number.
–324 + 17 = –307
So, the correct answer is C.