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EXAMPLE 6: Simplify: 5 1 - 3 1 + 3 1 + 4. 4 1
6 4 4 JUST TRY1: Find the sum of 9 + 9 .
SOLUTION: we have:
1 1 1 [ 12 ÷ 6 = 2, 2 × 31 = 62] , JUST TRY 2: 1 2 .
5 - 3 + 3 + 4. Find the sum of 3 5 and 6 5
6 4 4 { [ 12 ÷ 4 = 3, 3 × 13 = 39] }
31 13 10 4 [ 12 ÷ 3 = 4, 4 × 10 = 40] 6 13
= - + + JUST TRY 3: Subtract from .
6 4 3 1 [ 12 ÷ 1 = 12, 12 × 4 = 48] 15 15
62 - 39 + 40 + 48 1 2
= JUST TRY 4: Subtract 1 from 5 .
12 3 3
150 - 39 111 37 37 1 2 3
= = = = 9 JUST TRY 5: Add and .
12 12 4 4 3 5
4
3 1
JUST TRY 6: Add 2 and 4 .
4 8
5 9
EXAMPLE 7: Of, and which ts greater and by how much?
7 14 PRACTICE EXERCISE 5.3
5 9
SOLUTION: Let us compare and
7 14
5 × 14 = 70 and 7 × 9 = 63. 1 . Add the following fractions and reduce them to the lowest terms.
5 9 5 3 3 5 1 3 2 1 5 3 1
Clearly, 70 > 63; > (a) 12 + 12 (b) 11 + 11 + 11 (c) 7 + 5 + 10 (d) 1 8 + 2 4 + 3 12
7 14
5 9 (e) 2 + 3 1 + 4 1 + 5 1
Required difference = 7 - 14 2 3 4
10 - 9 2. Subtract the following fractions and reduce them to the lowest terms.
= { [ 14 ÷ 7 = 2, 2 × 5 = 10] and }
14 [ 14 ÷ 14 = 1, 1 × 9 = 9] (a) 8 - 4 (b) 11 - 9 (c) 5 2 - 3 1 (d) 3 3 - 1 1 (e) 7 1 - 4 1
1 15 15 25 25 3 3 5 15 6 18
=
4
3. Simplify the following and reduce them to the lowest terms.
Hence, 5 is greater than. 9 by 1 (a) 4 + 2 - 3 (b) 11 - 4 + 6 (c) 3 1 + 2 4 - 1 1 (d) 3 21 + 201 - 431
7 14 14 5 5 5 21 21 21 2 5 2 10 100 200
2 1 (e) 4 3 + 2 5 - 1 1
EXAMPLE 8: The cost of a pen is ₹ 6 and that of a pencil is ₹ 4 6 Which costs more and by how 35 7 5
much? 3 4. Tapur and Tupur anted to gift a shawl to their mother. Tapur knitted 3 th of the shawl and Tupur 1
2 20 ( 20 × 2 ) 40 5 5 th
SOLUTION: Cost of a pen = ₹ 6 = ₹ = ₹ = is the shawl complete? If not, how much of the knitting is yet to be done for the gift to be ready?
3 3 ( 3 × 2 ) 6 1 1
40 25 2 1 5. Seema and Reena go for jogging. Seema jogs for 2 5 km and Reena 2 7 km. Who jogs more and by
Clearly, > and so ₹ 6 > 4 how much?
6 6 3 6
So, the cost of a pen is more than the cost of a pencil. 6. Mini bought 5 litres of oil. She used 3 3 litres of oil for cooking during the month. How much oil is left
5
Difference between their costs = ₹ ( 20 - 25 ) ( 40 - 25 ) at the end of the month? 3 1
1
6
3
15 3 1 6 7. Vinita bought 5 2 kg of guavas, 3 4 kg of apples and 4 4 kg of oranges. Find the total weight of the
fruits bought by her.
= ₹ = ₹ 2 = ₹ 2 .
6 6 6
1
Hence, the cost of a pen is more than the cost of a pencil by ₹ 2 .
2