Basic Mathematics for College Students

148 Chapter 2 The Integers

EXAMPLE (^3) Add: a. b. c.
StrategyWe will use the rule for adding two integers that have different signs.
WHYIn each case, we are asked to add a positive integer and a negative integer.
Solution
a.Find the absolute values: and
b.Find the absolute values: and
c.Find the absolute values: and
568
 206
362
Subtract the smaller absolute value from the
larger: 568  206 362. Since the positive
number, 568, has the larger absolute value, the
answer is positive.

 206  568  362

0  2060  206 05680  568

4

3

1

11

 17

24

Subtract the smaller absolute value from the

larger: 41  17 24. Since the negative number,

41, has the larger absolute value, make the final

answer negative.

 41  17  24

0  410  41 0170  17

Subtract the smaller absolute value from the larger:

8  4 4. Since the positive number, 8, has the

larger absolute value, the final answer is positive.

8 (4) 4

080  8 0  40  4

8 (4)  41  17  206  568

Self Check 3

Add:

a.

b.

c.

Now TryProblems 33, 35, and 39

 506  888

 53  39

7 (2)

Caution! Did you notice that the answers to the addition problems in

Examples 2 and 3 were found using subtraction? This is the case when the

addition involves two integers that have different signs.

“College can be trial by fire — a test of how to cope with pressure, freedom,

distractions, and a flood of credit card offers. It’s easy to get into a cycle of

overspending and unnecessary debt as a student.”

Planning for College,Wells Fargo Bank

If your income is less than your expenses, you have a negativecash flow. A

negative cash flow can be a red flag that you should increase your income

and/or reduce your expenses. Which of the following activities can increase

income and which can decrease expenses?

• Buy generic or store-brand items.


• Get training and/or more education.


• Use your student ID to get discounts at stores, events, etc.


• Work more hours.


• Turn a hobby or skill into a money-making business.


• Tutor young students.


• Stop expensive habits, like smoking, buying snacks every day, etc


• Attend free activities and free or discounted days at local attractions.


• Sell rarely used items, like an old CD player.


• Compare the prices of at least three products or at three stores before
  buying.
  Based on the Building Financial Skillsby National Endowment for Financial Education.

THINK IT THROUGH Cash Flow