1. Adding Different Units
Before performing calculations that involve two different length
units, convert either one of the units or both so that the units are
the same. (Most often use the smaller units.)
Perform the following calculations:
1. 2 m + 75 cm = ___________________
2. 3 ft 2 in + 7 ft 11 in = ___________________
3. 3 mi ­ 250 ft = ___________________
4. 12 mm x 4.3 cm = ___________________
5. A roll of fencing is 90 m long and someone buys 536 cm. How
much is left on the roll?
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2. Solutions
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2)
3)
4)
5)
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3. Comparing Metric and Imperial Units
Use the ruler below to compare imperial linear measure
to metric linear measure. What is the approximate
relationship between an inch and a centimetre?
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4. Common Conversions
1 inch = 2.54 cm 1 mm= 0.04"
1 foot = 30.48 cm 1 cm = 0.39"
1 yard = 0.914 m 1 m = 39.37" = 3.28'
1 mile = 1.61 km 1 m = 1.09 yd
1 km = 0.621 mi
Example:
Convert 6 " into cm.
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5. Convert
a) 34 cm = ______________ft
b) 5 ft = _________________cm
c) 65 km = ________________miles
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6. Example 2
Your room measures 5 m by 8 m. You found carpet that is sold
in square yards. How many square yards will you need?
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7. Example 3
Convert 70 mi/h to km/hr.
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8. Drill Bit Conversion
A mechanic is doing a job that requires a 3 mm drill bit. He has
no metric drill bits.
He has no metric drill bits, but he does have the following
imperial sizes: 1/16", 1/8", 3/16". Which of these drill bits is the
nearest in size to 3 mm? (1 mm = 0.04 in)
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9. Solution
The mechanic wants to convert 3mm to inches.
3 mm x conversion factor of 0.04 = 0.12". Then we
have to convert the decimal to a fraction.
1/16" = 0.0625"
1/8" = 0.125"
3/16" = 0.1875"
The closest is 1/8" since 3 mm is 3 x 0.04" = 0.12".
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10. Homework:
Finish page 213 questions 1­6
Do p 218 questions 1­4
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