## Chapter 2 Fractions and Decimals Exercise 2.5

**Question 1: Which is greater?(i) 0.5 or 0.05Answer:**

0.5 = 5/10

0.05 = 5/100

LCM of 10, 100 = 100

= 5/10 × 10/10 = 50/100

= 5/100 × 1/1 = 5/100

Comparing 50/100 [] 5/100

50/100 > 5/100

Therefore, 0.5 is greater.

**(ii) 0.7 or 0.5**

Answer:

Answer:

0.7 = 7/10

0.5 = 5/10

Comparing 7/10 [] 5/10

70/10 > 5/10

Therefore, 0.7 is greater.

**(iii) 7 or 0.7**

Answer:

Answer:

0.5 = 7/1

0.7 = 7/10

LCM of 1, 10 = 10

= 7/1 × 10/10 = 70/10

= 7/10 × 1/1 = 7/10

Comparing 70/10 [] 7/10

70/10 > 7/10

Therefore, 7 is greater.

**(iv) 1.37 or 1.49**

Answer:

Answer:

1.37 = 137/100

1.49 = 149/100

LCM of 100, 100 = 100

= 137/100 × 1/1 = 137/100

= 149/100 × 1/1 = 149/100

Comparing 137/100 [] 149/100

137/100 < 149/100

Therefore, 1.49 is greater.

**(v) 2.03 or 2.30**

Answer:

Answer:

2.03 = 203/100

2.30 = 230/100

LCM of 100, 100 = 100

= 203/100 × 1/1 = 203/100

= 230/100 × 1/1 = 230/100

Comparing 203/100 [] 230/100

203/100 < 230/100

Therefore, 2.30 is greater.

**(vi) 0.8 or 0.88**

Answer:

Answer:

0.8 = 8/10

0.88 = 88/100

LCM of 10, 100 = 100

= 8/10 × 10/10 = 80/100

= 88/100 × 1/1 = 88/100

Comparing 80/100 [] 88/100

80/100 < 88/100

Therefore, 0.88 is greater.

**Question 2: Express as rupees as decimals:**

(i) 7 paise

Answer:

(i) 7 paise

Answer:

= ₹ 1 = 100 paise

= 1 paise = ₹ 1/100

7 paise = ₹ 7/100

= ₹ 0.07

**(ii) 7 rupees 7 paise**

Answer:

Answer:

= ₹ 1 = 100 paise

= 1 paise = ₹ 1/100

7 rupees 7 paise = ₹ 7 + ₹ 7/100

= ₹ 7 + ₹ 0.07

= ₹ 7.07

**(iii) 77 rupees 77 paise**

Answer:

Answer:

= ₹ 1 = 100 paise

= 1 paise = ₹ 1/100

77 rupees 77 paise = ₹ 77 + ₹ 77/100

= ₹ 77 + ₹ 0.77

= ₹ 77.77

**(iv) 50 paise**

Answer:

Answer:

= ₹ 1 = 100 paise

= 1 paise = ₹ 1/100

50 paise = ₹ 50/100

= ₹ 0.50

**(v) 235 paise**

Answer:

Answer:

= ₹ 1 = 100 paise

= 1 paise = ₹ 1/100

235 paise = ₹ 235/100

= ₹ 2.35

**Question 3: (i) Express 5 cm in meter and kilometer**

Answer:

Answer:

= 1 meter = 100 cm

= 1 cm = 1/100 m

= 5 cm = 5/100

= 0.05 m

Therefore, 5 cm is equal to 0.05 m.

= 1 km = 1000 m

= 1 m = 1/1000 km

= 0.05 m = 0.05/1000

= 0.00005 km

Therefore, 5 cm is equal to 0.00005 km.

**(ii) Express 35 mm in cm, m and km**

Answer:

Answer:

= 1 cm = 10 mm

= 1 mm = 1/10 cm

= 35 mm = 35/10 cm

= 3.5 cm

Therefore, 35 mm is equal to 3.5 cm.

= 1 meter = 100 cm

= 1 cm = 1/100 m

= 3.5 cm = 3.5/100 m

= 35/1000 m

= 0.035 m

Therefore, 35 mm is equal to 0.035 m.

= 1 km = 1000 m

= 1 m = 1/1000 km

= 0.035 m = 0.035/1000

= 0. 000035 km

Therefore, 35 mm is equal to 0. 000035 km.

**Question 4: Express in kg:**

(i) 200 g

Answer:

(i) 200 g

Answer:

= 1 kg = 1000 g

= 1 g = 1/1000 kg

= 200 g = 200/1000 kg

= 2/10

= 0.2 kg

**(ii) 3470 g**

Answer:

Answer:

= 1 kg = 1000 g

= 1 g = 1/1000 kg

= 3470 g = 3470/1000 kg

= 347/100

= 3.47 kg

**(iii) 4 kg 8 g**

Answer:

Answer:

= 1 kg = 1000 g

= 1 g = 1/1000 kg

= 4 kg 8 g = 4 kg + 8/1000 kg

= 4 kg + 0.008

= 4.008 kg

**Question 5: Write the following decimal numbers in the expanded form:**

(i) 20.03

Answer:20.03 = (2 × 10) + (0 × 1) + (0 × 1/10) + (3 × 1/100)

(i) 20.03

Answer:

**(ii) 2.03**

Answer:2.03 = (2 × 1) + (0 × 1/10) + (3 × 1/100)

Answer:

**(iii) 200.03**

Answer:200.03 = (2 × 100) + (0 × 10) + (0 × 1) + (0 × 1/10) + (3 × 1/100)

Answer:

**(iv) 2.034**

Answer:2.034 = (2 × 1) + (0 × 1/10) + (3 × 1/100) + (4 × 1/1000)

Answer:

**Question 6: Write the place value of 2 in the following decimal numbers:**

(i) 2.56

Answer:The place value of 2 in 2.56 is ones.

(i) 2.56

Answer:

**(ii) 21.37**

Answer:The place value of 2 in 21.37 is tens.

Answer:

**(iii) 10.25**

Answer:The place value of 2 in 10.25 is tenths.

Answer:

**(iv) 9.42**

Answer:The place value of 2 in 9.42 is hundredth.

Answer:

**(v) 63.352**

Answer:The place value of 2 in 63.352 is thousandth.

Answer:

**Question 7: Dinesh went from place A to place B and from there to place C. A is 7.5 km from B and B is 12.7 km from C. Ayub went from place A to place D and from there to place C. D is 9.3 km from A and C is 11.8 km from D. Who travelled more and by how much?**

**Answer:**

Distance between A and B = 7.5 km

Distance between B and C = 12.7 km

Distance between D and A = 11.8 km

Distance between C and D = 11.8 km

Distance travelled by Dinesh = AB + BC

= 7.5 + 12.7

= 20.2 km

Therefore, Dinesh travelled 20.2 km.

Distance travelled by Ayub = AD + DC

= 9.3 + 11.8

= 21.1 km

Therefore, Ayub travelled 21.1 km.

Comparing 20.2 km [] 21.1 km

= 20.2 km < 21.1 km

Therefore, Ayub travelled more distance.

= 21.1 km - 20.2 km

= 0.9 km

Therefore, Ayub travelled 0.9 km more than Dinesh.

**Question 8: Shyama bought 5 kg 300 g apples and 3 kg 250 g mangoes. Sarala bought 4 kg 800 g oranges and 4 kg 150 g bananas. Who bought more fruits?**

Answer:

Answer:

Shyama

Weight of Apples brought = 5 kg 300 g

Weight of Mangoes brought = 3 kg 250 g

Total weight brought by him = ?

= 5 kg 300 g + 3 kg 250 g = 8 kg 550 g

Sarala

Weight of Oranges brought = 4 kg 800 g

Weight of Bananas brought = 4 kg 150 g

Total weight brought by him = ?

= 4 kg 800 g + 4 kg 150 g = 8 kg 950 g

Comparing 8 kg 550 g (Shyama) [] 8 kg 950 g (Sarala)

= 8 kg 550 g (Shyama) < 8 kg 950 g (Sarala)

Therefore, Sarala bought more fruits.

**Question 9: How much less is 28 km than 42.6 km?**

Answer:

Answer:

= 42.6 km - 28 km

= 14.6

Therefore, 14.6 km less is 28 km than 42.6 km.

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