7th Grade Math

POPULATION About _^6

100

of the population of the United States

lives in Florida. Another _^4

100

lives in Ohio. How much more of

the U.S. population lives in Florida than in Ohio?

_^6

100

• ^4
  100
  = ^6 -^4
  100
  Subtract the numerators.

= _^2

100

or _^1

50

Simplify.

About _^1

50

more of the U.S. population lives in Florida than in Ohio.

Check 6 hundredths minus 4 hundredths equals 2 hundredths. ✓

j. JUICE Two-fifths quart of pineapple juice was added to a bowl

containing _^3

5

quart of orange juice. How many total quarts of

pineapple juice and orange juice are in the bowl?

Examples 1–5 Add or subtract. Write in simplest form.

1. 
   

   ^35 + ^15 2. ^27 + 71 33 - 43 + (- ^34 )

   
   


2. 
   

   ^38 - ^18 5. - ^45 - (^) (- 51 ) 6. 72 - 76
   Example 6 7. STATES Of the 50 states in
   WA
   OR
   CA
   ID
   MT
   NV UT
   AZ
   CO
   WY
   NM
   TX
   OK
   KS
   NE
   SD
   ND MN
   WI
   IL
   MO
   AR
   LAMSAL
   NC
   VA
   MI PANY
   DE
   NH
   MA
   ME
   TN
   KYWV
   IA
   SC
   NJ
   GA
   FL
   INOH MD
   CTRI
   the United States, 14 have an VT
   Atlantic Ocean coastline and
   5 have a Pacific Ocean coastline.
   What fraction of U.S. states
   have either an Atlantic Ocean
   or Pacific Ocean coastline?

   
   


3. 
   

   LUNCH The table shows the lunch Lunch Count
   Class Buying Packing
   Mrs. Savage 15 10
   Mr. LeGault 19 8
   Miss Cappizella 12 12

   
   

count for three seventh-grade classes.

Write the fraction in simplest form

that represents how much more of the

seventh-grade class is buying lunch

rather than packing.

Lesson 2A Add and Subtract Fractions 141

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