7. Fractions
Answers to all questions on fractional units, mixed fractions, equivalent fractions, comparing, adding and subtracting fractions. CBSE / NCERT Class 6 Ganita Prakash.
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7.1 Fractional Units and Equal Shares — Figure it Out
Each guava weighs about 13 kg.
Each packet weighs 14 kg.
3 ÷ 4 = 34 glass each.
12 + 14 = 24 + 14 = 34 kg
Quarter (14) < half (12) < three quarters (34) < one and a quarter (114) < one and a half (112) < two and a half (212)
7.2 Fractional Units as Parts of a Whole
Yes. Each piece is one of 6 equal parts of the same chikki, so each is 16 of it, even though the shapes are different.
(a) 112 (b) 14 (c) 18 (d) 16
(e) 18 (f) 16 (g) 124 (h) 124
7.3 Measuring Using Fractional Units
1 × 18 = 18
2 × 18 = 28 3 × 18 = 38
4 × 18 = 48 5 × 18 = 58
6 × 18 = 68 7 × 18 = 78
8 × 18 = 88 = 1
7.3 — Figure it Out
12 + 12 + 12 + 12 + 12 + 12 = 6 times half = 3
12 + 12 + 12 + 12 + 12 + 12 + 12 = 7 times half = 312
14 = 1 times quarter
14 + 14 = 2 times quarter = 24
14 + 14 + 14 = 3 times quarter = 34
14 + 14 + 14 + 14 = 4 times quarter = 1
Fold the strip into 3 equal parts (like folding a letter). Each part is 13.
Now fold the strip in half again. Each part becomes 16. Yes, 16 can be made from 13.
(a) 14 + 14 + 14 + 14 + 14 = 54 = 1 roti and 14 roti
(b) 14 added 9 times = 94 = 2 rotis and 14 roti
Draw rotis cut into 4 equal parts and shade the required number of parts.
13 → third circle (3 equal parts)
15 → fourth circle (5 equal parts)
18 → first circle (8 equal parts)
16 → second circle (6 equal parts)
7.4 Marking Fraction Lengths on the Number Line
1. Unit divided into 3 parts: the blue line is 23 unit long.
2. Unit divided into 5 parts: the blue lines are 25 and 45 unit long.
3. Unit divided into 8 parts: the marks are 18, 28, 38, 48, 58, 68, 78.
7.4 — Figure it Out
Divide 0 to 1 into 10 equal parts. Draw lines up to the 1st mark (110) and the 3rd mark (310).
For 45, divide 0 to 1 into 5 equal parts and draw a line up to the 4th mark. (It is the same as 810.)
For example: 14, 12, 23, 56, 32. Divide each unit into the required number of equal parts and mark them.
Countless (infinitely many). We can always divide a unit into more and more equal parts, for example 12, 13, 1100, 11000, …
The black line is 32 units long (3 half units).
65, 75, 85, 95
7.5 Mixed Fractions — Figure it Out
72 = 3 + 12. So there are 3 whole units.
43 = 1 + 13 → 1 whole unit
73 = 2 + 13 → 2 whole units
(a) 83 = 2 + 23 → 2 (b) 115 = 2 + 15 → 2 (c) 94 = 2 + 14 → 2
Yes, every fraction greater than 1 can be written as a whole number and a fraction less than 1.
But if the fraction is exactly a whole number, like 63 = 2, there is no fractional part left.
(a) 412 (b) 145 (c) 1219
(d) 529 (e) 1111 (f) 316
(a) 314 = 3 × 4 + 14 = 134
(b) 723 = 7 × 3 + 23 = 233
(c) 949 = 9 × 9 + 49 = 859
(d) 316 = 3 × 6 + 16 = 196
(e) 2311 = 2 × 11 + 311 = 2511
(f) 3910 = 3 × 10 + 910 = 3910
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7.6 Equivalent Fractions
1. Yes, 12 and 36 are equal lengths.
2. Yes, 23 and 46 are equivalent. They have the same length on the fraction wall.
3. 3 pieces of 16 make 12.
4. 2 pieces of 16 make 13.
Yes. Each of them is equal to 12. They have the same length on the fraction wall.
13 and 412
46 = 23 = 69 = 812 = 1015 = 1218 = …
Equivalent Fractions using Equal Shares — Figure it Out
Each child gets 34 roti.
Division fact: 3 ÷ 4 = 34
Addition fact: 34 + 34 + 34 + 34 = 3
Multiplication fact: 4 × 34 = 3
Each child gets 24 = 12 roti.
Division fact: 2 ÷ 4 = 24 = 12
Addition fact: 12 + 12 + 12 + 12 = 2
Multiplication fact: 4 × 12 = 2
Anil gets 25 cake.
With 10 children, 4 cakes are needed. So 25 = 410.
48, 510, 612, 1020
Each child gets 23 roti in every case, so the shares are the same: 23 = 46 = 69.
In 46 and 69, the numerator and denominator of 23 are multiplied by the same number (2 and 3).
(a) 5 glasses among 4 friends = 10 glasses among 8 friends. So 54 = 108.
(b) 4 kg in 3 bags = 12 kg in 9 bags. So 43 = 129.
(c) 7 rotis among 5 children = 14 rotis among 10 children. So 75 = 1410.
Each child gets a bigger share, because more units are shared among the same number of children.
12 = 48, and 5 units among 8 is more than 4 units among 8. So 12 < 58.
1. Group 1: 34 = 3040; Group 2: 710 = 2840. Group 1 gets more.
2. Group 1: 47; Group 2: 57. Group 2 gets more.
The second pair was easier to compare, because the number of children (denominator) was the same.
| Pair | Same fractional unit |
|---|---|
| 72 and 35 | 3510 and 610 |
| 83 and 56 | 166 and 56 |
| 34 and 35 | 1520 and 1220 |
| 67 and 85 | 3035 and 5635 |
| 94 and 52 | 94 and 104 |
| 110 and 29 | 990 and 2090 |
| 83 and 114 | 3212 and 3312 |
| 136 and 19 | 3918 and 218 |
Lowest Terms — Figure it Out
(a) Divide by 17: 1751 = 13
(b) Divide by 16: 64144 = 49
(c) Divide by 21: 126147 = 67
(d) Divide by 7: 525112 = 7516
7.7 Comparing Fractions — Figure it Out
(a) 166 and 156. So 83 > 52
(b) 2863 and 2763. So 49 > 37
(c) 4970 and 4570. So 710 > 914
(d) Same denominator, 12 > 8. So 125 > 85
(e) 52 = 104. So 94 < 52
(a) 2130, 2230, 1230 → 25 < 710 < 1115
(b) 1924, 2024, 1424 → 712 < 1924 < 56
(a) 5032, 2832, 10432, 1732 → 134 > 2516 > 78 > 1732
(b) 4560, 14460, 3560, 7560 → 125 > 54 > 34 > 712
7.8 Addition and Subtraction of Fractions
Eaten = 34. Remaining = 1 − 34 = 14 of the chikki.
Start at 47 and move 6 more steps of 17. We reach 107 = 137. Yes, the answer is the same.
Addition — Figure it Out
(a) 27 + 57 + 67 = 137 = 167
(b) 912 + 412 = 1312 = 1112
(c) 46 + 56 = 96 = 32 = 112
(d) 1421 + 621 = 2021
(e) 4560 + 2060 + 1260 = 7760 = 11760
(f) 1015 + 1215 = 2215 = 1715
(g) 1215 + 1015 = 2215 = 1715
(h) 2440 + 2540 = 4940 = 1940
(i) 184 + 54 = 234 = 534
(j) 5621 + 621 = 6221 = 22021
(k) 4560 + 2060 + 1260 = 7760 = 11760
(l) 70105 + 84105 + 45105 = 199105 = 194105
(m) 5412 + 1512 + 1412 = 8312 = 61112
23 + 34 = 812 + 912 = 1712 = 1512 litres
25 + 34 = 820 + 1520 = 2320 = 1320 m
Yes, it is sufficient, because 1320 m is more than 1 m.
Subtraction — Figure it Out
1. 28 = 14
2. 29
3. 927 = 13
(a) 515 = 13
(b) 615 − 415 = 215
(c) 1518 − 818 = 718
(d) 46 − 36 = 16
(a) 103 − 134 = 4012 − 3912 = 112
(b) 233 − 185 = 11515 − 5415 = 6115 = 4115
(c) 457 − 297 = 167 = 227
(a) 710 − 12 = 710 − 510 = 210 = 15 km
(b) 103 = 4012 and 134 = 3912. Namit takes less time, by 112 minute.
Puzzle!
12 + 13 + 16 = 36 + 26 + 16 = 1
12 + 13 + 17 + 142
12 + 13 + 18 + 124
12 + 13 + 19 + 118
12 + 13 + 110 + 115
12 + 14 + 15 + 120
12 + 14 + 16 + 112