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Unit review: operations with fractions
Textbook: Part 3, unit review, pp. 93–94
GoalReview of operations with fractions: adding, subtracting, regrouping, multiplying by a whole number.
New words
review · takrorlashaddition · qo‘shishsubtraction · ayirishmultiplication · ko‘paytirish
Explanation
In this unit we learned adding and subtracting fractions with equal denominators, adding and subtracting mixed numbers, subtracting from one and from a whole number, regrouping, and multiplying a fraction by a whole number. For each operation recall the rule, and remember to change results into mixed numbers and to check by the inverse operation.
Worked examples
5/11 + 8/11 − 4/11 = 9/11. 7 5/9 + 2 8/9 = 9 + 13/9 = 10 4/9.
10 − 4 3/7 = 9 7/7 − 4 3/7 = 5 4/7. 9/10 × 3 = 27/10 = 2 7/10.
Class activity
“Fraction quiz”: the class splits into two teams. The teacher gives addition, subtraction and multiplication examples one after another and teams solve them at the board.
Practice
1
Work out 5/11 + 8/11 − 4/11.
9/11
2
Work out 7 5/9 + 2 8/9.
10 4/9
3
Work out 10 − 4 3/7.
5 4/7
4
Work out 9/10 × 3 and write it as a mixed number.
27/10 = 2 7/10
5
There was 5 1/4 m of cloth. 2 3/4 m was used for a dress and 1 2/4 m for a skirt. How many metres are left?
1