7th Grade Math

Solve each equation. Check your solution.

B 25. a - 3.5 = 14.9 26. x - 2.8 = 9.5 27. r - 8.5 = - 2.1

28. z - 9.4 = - 3.6 29. n + 1.4 = 0.72 30. b + 2.25 = 1


29. m + 65 = 1211 32. y + ^12 = ^34 33. s - 91 = 185


30. 
    
    
    
    • ^13 = r - ^34 35. - ^56 + c = - ^1112 36. - ^3334 = t - 1713
    
    
    
    

Write an equation. Then solve the equation.

37. MONEY Suppose you have d dollars. After you pay your sister the $5
    you owe her, you have $18 left. How much money did you have?


38. FINANCIAL LITERACY Suppose you have saved $38. How much more do
    you need to save to buy a small television that costs $65?


39. GEOMETRY The sum of the measures of
    the angles of a triangle is 180°. Find the
    missing measure.

x°

35 ° 45 °

40. VOLCANOES Alaska, Hawaii, and Washington have active volcanoes.
    Alaska has 43, Hawaii has 5, and Washington has v. If they have 52 active
    volcanoes in all, how many volcanoes does Washington have?

(^4141) GOLF The table shows Cristie Kerr’s scores for four
rounds of a recent U.S. Women’s Open. Her total
score was even with par. What was her score for the
third round?
Round Score
First - 1
Second - 3
Third s

42. BUSINESS At the end of the day, the closing price of Fourth + 2
    XYZ Stock was $62.87 per share. This was $0.62 less
    than the opening price. Find the opening price.


43. MULTIPLE REPRESENTATIONS The table shows information about the
    tallest wooden roller coasters.

Tallest Wooden

Roller Coasters

Height

(feet)

Drop

(feet)

Speed

(mph)

Son of Beast 218 214 s

El Toro 181 176 70

The Rattler 180 d 65

Voyage 173 154 67

Colossos h 159 75

a. ALGEBRA The difference in speeds of Son of Beast and The Rattler is

13 miles per hour. If Son of Beast has the greater speed, write and

solve a subtraction equation to find its speed.

b. BAR DIAGRAM The Rattler has a drop that is 52 feet less than El Toro.

Draw a bar diagram and write an equation to find the height of The

Rattler.

c. ALGEBRA Let h represent the height of the Colossos roller coaster.

Explain why h + 10 = 180 and h + 48 = 218 are equivalent equations.

Then explain the meaning of the solution.

212 Equations and Inequalities

Real-World Link

Cristie Kerr

donates $50 to

breast cancer

research for

every birdie she

makes.

RR

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