Page 94 - classs 6 a_Neat

JUST TRY:1 a. Which number is greater, 10.51 or 10.81? OPERATIONS ON DECIMALS
b. Which number is greater, 2.563 or 2.561?
JUST TRY: 2 Convert 2.5 into a fraction.
JUST TRY: 3 Convert 1.35 into a fraction. ADDITION OF DECIMALS
JUST TRY: 4 Convert 4.127 into a fraction. METHOD:
Step 1. Convert the given decimals into like decimals.
PRACTICE EXERCISE 6.2 Step 2. Write the addends one under the other in column form, keeping the decimal points of all the addends in
the same column and the digits of the same place in the same column.
Step 3. Add as in the case of whole numbers.
1. Compare the following decimal fractions by using >, = or < symbols. Step 4. In the sum, put the decimal point directly under decimal points in the addends.
a.0.3 ₹ 3.0 b.72.9 ₹7.29 c.8.88 ₹ 8.880 d.70. 7 ₹ 70.08 e.6.359 ₹ 6.4
The following examples will make the ideas more clear.
2. Convert the following unlike decimals into like decimals.
a.1.2, 2.15, 5.631 b. 0.8, 10.81, 10.801 c. 6.35, 6.53, 6.5, 6.513 EXAMPLE 1: Add: 27.8, 46,175.09 and 685.7
d.9.01, 9.001, 9.1, 9.10 e.49.9, 4.99, 0.499
SOLUTION: Converting the given decimals into like decimals, we get
3. Arrange the following decimals in ascending order. 27.80, 46.00, 175.09 and 685.70.
a.0.05, 0.15, 5.115, 5.005 b.7.39, 7.19, 17.309, 17.390 c. 10.0, 10.01, 10.1, 10.105 Writing these decimals in column form and adding, we get:
d.55.5, 5.55, 0.555, 5550 e.14.2, 14.25, 14.27, 1.427 27.80
46.00
4. Arrange the following decimals in descending order. 175.09
a.4.23, 4.2, 42.3, 0.423, 42.0 b.0.19, 0.21, 1.21, 1.91, 0.03 C. 55.6, 6.56, 66.5, 666.5, 0.665 685.70
d. 89.1, 89.2, 89.02, 89.03, 89.01 e.19.91, 1.999, 199.1, 1991 934.59
Hence, the sum of the given decimals is 934.59.
5. Convert the following decimals into fractions.
a. 1.9 b. 0.27 c. 333.3 d. 87.003 e. 4.125 EXAMPLE 2: Add: 67.25, 249, 8.785, 9.8 and 0.23

6. Convert the following fractions into decimals. SOLUTION: Converting the given decimals into like decimals, we get
17 157 257 2468 2,219 67.250, 249.000, 8. 785, 9.800 and 0.230.
(a) (b) (c) (d) (e)
10 10 100 100 1000 Writing these decimals in column form and adding, we get:
7. Convert the following fractions into decimals by changing the denominator into 10 or multiples of 67.250
10. 4 9 9 209 43 249.000
(a) (b) (c) (d) (e) 8.785
5 4 125 500 50 9.800
8. Convert the following fractions into decimals by the long division method. 0.230
3 3 3 1 4 335.065
(a) 9 (b) 2 (c) 13 (d) 70 (e) 7
5 50 8 4 25 EXAMPLE 3: A man covers a journey by car in 3 hours. He covers a distance of 64 km 324 m
9. Write any three decimals less than each of the following. during the first hour, 58 km 56 m during the second hour and 62 km 8 m during the
a. 0.65 b. 0.789 c. 0.9 d. 4.1 e. 12.11 third hour. What is the length of his Journey?

10. Write any three decimals more than each of the following. SOLUTION: We have:
a. 4.6 b. 82.3 c. 987.1 d. 19.4 e. 0.001 distance covered during the first hour = 64.324 km
distance covered during the second hour = 58.056 km
distance covered during the third hour = 62.008 km
Total distance covered in 3 hours = 184.388 km
Hence, the length of his Journey = 184.388 km
= 184 km 388 m.