1. Converting Units Likely the most useful thing you will learn all year.

2. Lecture Part A. ( Just watch and think ) A sign along the road in Canada says “100 kilometers/hour.” What is this in miles per hour?

4. =

5. =

6. =

7. =

9. 1.61 km = 1 mile & 1 km = 0.621 miles =

10. 1.61 km = 1 mile & 1 km = 0.621 miles =

11. =

12. Lecture Part B. ( Just watch and think ) An airplane has a speed of 600 miles per hour. How fast is this in miles per minute?

14. =

15. =

16. =

17. =

18. = 1 hour = 60 minutes

19. =

20. = 10 miles/min is the same speed as 600 miles/hour

21. = Wait a tick… Why does this method work?

22. x ÷ x = ?

23. = ?

24. = 1

25. = This method works because when you multiply by 1 you do not change the value of the quantity. 1

26. 1a. The piece of paper on your desk is 8 1 / 2 inches by 11 inches. In centimeters, how wide is the page?

28. = cm

31. How many centimeters equals how many inches? = cm

33. 2.54 centimeters = 1 inch = cm

34. 2.54 centimeters = 1 inch

35. = 21.6 cm The piece of paper is 21.6 cm wide.

36. 1b. What is the width of the page, in feet?

37. What is the width of the page, in feet? What should we start with: 8.50 inches, or 21.6 cm?

39. = ft

42. How many feet equals how many inches? = ft

44. 1 foot = 12 inches = ft

45. 1 foot = 12 inches

46. = ft

47. = 0.708 ft The page is 0.708 feet long

48. 2a. A football field is 100 yards. How many inches is this?

49. = inches

52. = 3600 inches

53. 2b. How many kilometers long is a football field?

54. = km

57. = 0.09144 km

58. 2c. Looking for some extra practice? How long is a football field in: Miles Meters Inches Centimeters

59. 2c. Answers: Miles [0.057] Meters [91.44] Inches [3600] Centimeters [9144]

60. 3. A student is 17 years old. How many hours old is the student?

61. =

62. = hours

67. = 148,920 hours

68. 4. A sprinter is running at 10 m/s. How fast is this, in miles per hour?

70. miles =per hour

71. miles =per hour

73. miles =per hour

74. miles = 22 per hour

75. 5. A hotel room in Paris is 110 Euros. How much is this in US Dollars?

76. €110

77. = $

78. €110 = $

79. 1 Euro = 1.4 Dollars 1 Dollar = 0.72 Euros €110 = $

80. 1 Euro = 1.4 Dollars 1 Dollar = 0.72 Euros €110 = $

81. 1 Euro = 1.4 Dollars 1 Dollar = 0.72 Euros €110 = $ 154

82. 6a. A shoe box is 5 inches x 3 inches x 11 inches = 165 cubic inches. How many cubic centimeters is this?

84. = cm 3

87. = 2700 cm 3

88. 6b. Extra practice: Your desktop is about 200 square inches. What is this area in square feet and square centimenters?

89. Answers. The area of your desktop is: 1.38 ft 2 1,290 cm 2

90. 7. The density of water is exactly 1 g/cm 3. What is the density of water in pounds per cubic foot?

91. = pounds per cubic foot

95. = 62 pounds per cubic foot

96. 8. A truck can unload 100 kg of stone in 2 minutes. How fast is this, in pounds per second?

97. = pounds / second

101. = 1.8 pounds / second

102. 9. A landscaper can move 2 kg of soil every minute. How many hours will it take to move 300 pounds?

104. = hours

108. = 1.1 hours

109. Estimating ≈

110. Which is greater: A.The number of pieces of printer paper, stacked from floor to ceiling. B.The number of walking steps from the High School to the Middle School. C.They are about the same.

111. How could we estimate option A.?

112. About how far is it from the floor to the ceiling? How tall is a package of paper?

113. = sheets

115. = 27,000 sheets

116. About how far away is the middle school? About how big is one step?

117. = steps

119. = 3,520 steps

120. btw, 27,000 steps ≈ distance from here to Solon, OH

121. Which is greater: A.The number of pieces of printer paper, stacked from floor to ceiling. B.The number of walking steps from the High School to the Middle School. C.They are about the same.

122. E1a. Estimate how many hours a McDonald’s worker must work to earn enough to buy a car. Assume that all the money goes toward the car. $

123. How much is a car? What is the wage of a McDonald’s worker?

124. = hours

126. = 1000 hours

127. E1b. How many years is this?

128. = years

130. = 0.48 years

131. E2. If you drove from here to San Francisco, about how many times would you stop for gas?

132. How far away is San Francisco? How far can you drive on one tank of gas? How far can you drive on one gallon of gas? How many gallons fit in a tank?

133. = tanks

135. = 8 tanks

136. E3. If you wanted to buy sliced turkey to feed the entire senior class, how much would that cost?

137. How many students is that? How much does each student need? What is the cost, per pound?

138. = $

140. = $ 500

141. E4a. About how many hours have you spent in school?

142. How many years have you been in school? How many days in a year? How many hours in a day?

143. = hours

145. = 15,000 hours

146. E4b. About what percentage of your life have you spent in school? %

147. How many hours old are you?

148. = 150,000 hours

150. E4c. What percentage of your waking life have you spent in school?

151. How many hours are you awake every day?

152. = hours

153. = 99,000 hours