FORMULAS

Formulas are equations that state rules about relationships

A = LW

Area of a rectangle  =  Length times Width

P = 2L + 2W

Perimeter of a rectangle = (2 x length) + (2 x width)

D = RT

Distance traveled = rate x time traveled

C = NP

Cost = number of items x price per item

 

Complete each statement with a variable expression

1.

 A rectangle has width 6 units and length x units.  Its area is   square units.

2.

 A rectangle has width y and length 14.  Its perimeter is   .

3.

 You travel for ( t - 2 ) hours at 75 miles/hour.  You travel   km.

4.

 You buy ( m + 5 ) bagels at 35 cents each.  The cost is   cents.

5.

 Al earns ( p + 3 ) dollars per hour.  In 8 hours he earns   dollars.

6.

 Our house is y years old.  Four years ago it was  years old.

7.

 The Golden Gate Bridge was built n years ago.  Three years from now it will have been standing  years.

8.

 A sports arena was d years old 15 years ago.  It is now years old.

9.

 Nine years from now Fenway Park will be g years old.  It is now  years old.

10.

 Mike jogs for half an hour at y miles an hour.  He jogs   miles.
11. Workers on an assembly line produce ( x + 10 ) cars each day.   In 5 days they produce   cars.
12. A conveyer belt moves at n yds./min.  In 10 minutes it moves   yds.
13. I drove for three hours at r miles/hour   How far did I go? 
14. Dick drove for h hours at 85 km/hour.  How far did he go?  
15. Pencils cost p cents each.  How much will 5 pencils cost?  
16. Yogurt costs 75 cents per container.  How much will x containers cost? 
17. Sketch a rectangle having length 1 and width 5.  What is its area? 
18. Sketch a rectangle having length 7 and width w.  What is its perimeter? 
19. Pencils cost p cents each and notebooks cost n cents each.   How much will 3 pencils and 2 notebooks cost? 
20. Shirts cost $20 each and ties cost $12 each.  How much will s shirts and t ties cost?