7th Grade Math

Use the work backward strategy to solve

Exercises 4–7.

4. MONEY Marisa spent $8 on a movie ticket.
   Then she spent $5 on popcorn and one half
   of what was left on a drink. She has $2 left.
   How much did she have initially?

55 NUMBER THEORY A number is multiplied

by -3. Then 6 is subtracted from the

product. After adding -7, the result is

• 
  
  
  
  25. What is the number?
  
  
  
  

6. TIME Timothy’s morning schedule is
   shown. At what time does Timothy wake
   up if he arrives at school at 9:00 a.m.?

Timothy’s Schedule

Activity Time

Wake up

Get ready for school — 45 min

Walk to school — 25 min 9:00 A.M.

7. LOGIC A small box contains 4 tennis balls.
   Six of these boxes are inside a medium
   box. Eight medium boxes are inside each
   large box, and 100 large boxes are shipped
   in a large truck. How many tennis balls are
   on the truck?

Use any strategy to solve Exercises 8–15.

8. GEOGRAPHY The land area of North Dakota
   is 68,976 square miles. This is about 7 times
   the land area of Vermont. Estimate the
   land area of Vermont.


9. AGE Brie is two years older than her sister
   Kiana. Kiana is 4 years older than their
   brother Jeron, who is 8 years younger than
   their brother Percy. Percy is 16 years old.
   How old is Brie?
   10. ELEVATION New Orleans, Lousiana, has an
   elevation of -8 feet related to sea level.
   Death Valley, California, is 274 feet lower
   than New Orleans. What is the elevation of
   Death Valley?
   11. GEOMETRY Draw the sixth figure in the
   pattern shown.
   12. WATERFALLS Angel Falls in Venezuela is
   3,212 feet high. It is 87 feet higher than
   2.5 times the height of the Empire State
   Building. Find the height of the Empire
   State Building.
   13. AIRCRAFT An aircraft carrier travels about
   6 inches per gallon of fuel. Raquel’s car
   travels about 28 miles per gallon of fuel.
   There are 5,280 feet in one mile. How
   many more inches per gallon does Raquel’s
   car get than an aircraft carrier?
   14. SCHOOL SUPPLIES Alexandra wishes to buy
   5 pens, 1 ruler, and 7 folders.

Item Cost

Pens $2.09

Ruler $0.99

Folder $1.19

If there is no tax, is $20 enough to pay for

Alexandra ’s school supplies? Explain your

reasoning.

15. MONEY Antonio has saved $27 in cash
    to spend at the arcade. If he has 10 bills,
    how many of each kind of bill does
    he have?

• Work backward.


• Look for a pattern.


• Draw a diagram.


• Choose an operation.

Lesson 1A Addition and Subtraction Equations 203

= Step-by-Step Solutions begin on page R1.

Extra Practice begins on page EP2.

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