confidential2 convert the following decimals to percent: 1.0.75 = 75% 2.0.0095 =.95% 3.0.439 = 43.9%...
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Confidential 2
Convert the following decimals to percent:
1. 0.75 = 75%2. 0.0095 = .95%3. 0.439 = 43.9%4. 0.422 = 42.2%5. 0.87 = 87%
Warm up
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Let’s Review what we have learned in the last
lesson• The decimal point separates the whole units on
the left from the decimal units on the right. • The numbers on the left side represent whole num
bers.• The numbers on the right side of the point are the
decimal values.
• The naming difference is in the "th“
• Percent means parts per hundred. • we use the symbol % for percent.
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• For converting decimals to percent •Multiply the decimal by 100 and put the %
sign
• For converting percent to decimals •First remove the Percent sign. •Divide by 100
Recap
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What is rate/unit rate?
A rate is a ratio that is used to compare different kinds of quantities.
A unit rate describes how many units of the first type of quantity corresponds to one unit of the second quantity.
Examples of unit rates: miles per hour, kilometers per hour, meter per seconds, cost per item, earnings per week, etc.
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Finding unit priceA unit price is a rate comparing the
price of an item to its unit of measure. To find the unit price of an item divide the
total cost by the number of items bought.
After finding the unit price we can also find the cost of more than one item– Multiply the unit price by the number of
items you are buying
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Price of 5 apples is $20. Find the unit price and find the price of 7 apples.
Unit price = 20/5 = $4 Price of 7 apples = 7 × 4 = $28 The price of 7 apples is $28.
To find the unit Price divide total cost by the number of items bought .
Example 1
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John can type 923 words in 13 minutes. Find how many words per minute can he type.
Unit rate = 923/13 = 71
John can type 71 words per minutes.
To find the unit rate divide total words by the number of minutes.
Example 2
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Distance, rate and time
Distance = Rate × time– To find distance multiply rate by time
Rate = Distance/time– To find rate divide distance by time
Time = Distance/rate– To find time divide distance by rate
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On a trip, Kate traveled 600 km. for 10 hours. Find her average speed?
Average Speed = Rate Rate = Distance/time Rate = 600/10 = 60 km. per hour
Kate’s average speed was 60 km./hour.
To find the rate divide distance by time .
Example 3
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Your Turn
Find the unit rate:
1. 72 seats in 9 rows 8 seats2. 160 miles in 5 hours 32mi/h3. 70 seats in 5 rows 14 seats4. 192 pages in 4 days 48 pages5. 320 meters in 5 seconds 64 m /s
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Your Turn
Find the unit rate:
6. 143 seats in 13 rows 11 seats7. 300 miles in 6 hours 50mi/h8. 350 words in 5 minutes 70 words9. 70 steps in 2 minutes 35 steps10.240 meters in 6 seconds 40 m /s
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Let us play a game
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1) Maria works in a book store and she earns $100 for 5hours of work. i) At this rate, how much would she earn in 8
hours?
ii) How many hours would it take to earn $250?
i) First find Maria's rate per hour. Rate per hour = 100/5 =$20 Earnings for 8 hours = 20 × 8 =$160
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ii) Divide total earnings by the rate. No. of hours = 260/20 = 13 hours
Maria worked for 13 hours to earn $260.
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2) A car travels east at a speed of 50 mph and a motorcycle travels west at a speed of 55 mph. If they start at the same time and place, how long will it take them to be 315 miles apart?
First let us draw a figure.
let they traveled for x hours.
50 mph55 mph
315 miles
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Distance traveled by car = rate × time Distance traveled by car = 50 × x = 50x
Distance traveled by motorcycle = rate × time Distance traveled by motorcycle = 55 × x = 55x Total distance= 315 50x + 55x =315 105x = 315 (divide both sides by 105) x = 3 hours
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3) The population of Alaska is 603,617 with 253,922 of those people living in Anchorage. The area of Alaska is 570,374 square miles. The area of Anchorage is 1,697.6 square miles.
a. Find the population density of Alaska
b. Find the population density of Anchorage
a.1.06 people per square mile
b. 149.58 people per square mile
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Let Us Review
A rate is a ratio that is used to compare different kinds of quantities.
A unit rate describes how many units of the first type of quantity corresponds to one unit of the second type of quantity.
A unit price is a rate comparing the price of an item to its unit of measure.
To find the unit price divide the total cost by the number of items bought.
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Let Us Review
Rate = Distance/time– To find rate divide distance by time
Time = Distance/rate– To find time divide distance by rate
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You had a Great Lesson Today!
Be sure to keep practicing