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Unit review: decimals and percent
Textbook: Part 3, unit review, pp. 116–117
GoalReview of decimals and percent: reading, writing, length and mass, percent.
New words
review · takrorlashdecimal · o‘nli kasrpercent · foizmeasurement · o‘lchov
Explanation
In this unit we learned the places of decimals (tenths, hundredths, thousandths), reading and writing decimals, expressing length and mass as decimals, and percent. When changing a decimal into a common fraction, the number of digits after the comma gives the number of zeros in the denominator.
Worked examples
4.05 = 4 5/100; 17 cm 3 mm = 17.3 cm.
5 kg 40 g = 5.04 kg; 25% of 800 g = 200 g.
Class activity
“Question relay”: two teams answer questions about decimals and percent at the board in turn; correct answers earn points.
Practice
1
Write 4.05 as a mixed number.
4 5/100
2
Write 17 cm 3 mm in centimetres as a decimal.
17.3
3
Write 5 kg 40 g in kilograms as a decimal.
5.04
4
Work out 2.8 + 4.5.
7.3
5
How many grams is 25% of 800 g of cheese?
200