Decimals - Exercise 3(F)

Round off the following to the nearest whole number :

87.46

Answer

The given number is 87.46. Its whole number part is 87.

First digit to the right of decimal is 4 < 5.

∴ Required rounded off number is 87.

Round off the following to the nearest whole number :

65.83

Answer

The given number is 65.83. Its whole number part is 65.

First digit to the right of decimal is 8 > 5.

So, we increase the whole number part by 1.

∴ Required rounded off number is 66.

Round off the following to the nearest whole number :

71.54

Answer

The given number is 71.54. Its whole number part is 71.

First digit to the right of decimal is 5.

So, we increase the whole number part by 1.

∴ Required rounded off number is 72.

Round off the following to the nearest whole number :

98.5

Answer

The given number is 98.5. Its whole number part is 98.

First digit to the right of decimal is 5.

So, we increase the whole number part by 1.

∴ Required rounded off number is 99.

Round off the following to the nearest whole number :

60.29

Answer

The given number is 60.29. Its whole number part is 60.

First digit to the right of decimal is 2 < 5.

∴ Required rounded off number is 60.

Round off :

6.342, correct to 2 decimal places

Answer

The given number is 6.342

This number up to 2 decimal places is 6.34

The third decimal place is 2 < 5

∴ The number correct to 2 decimal places is 6.34

Round off :

8.1347, correct to 3 decimal places

Answer

The given number is 8.1347

This number up to 3 decimal places is 8.134

The fourth decimal place is 7 > 5

So, we increase the 3rd decimal place by 1

∴ The number correct to 3 decimal places is 8.135

Round off :

0.845, correct to 2 decimal places

Answer

The given number is 0.845

This number up to 2 decimal places is 0.84

The third decimal place is 5

So, we increase the 2nd decimal place by 1

∴ The number correct to 2 decimal places is 0.85

Round off :

1.732, correct to 1 decimal place

Answer

The given number is 1.732

This number up to 1 decimal place is 1.7

The second decimal place is 3 < 5

∴ The number correct to 1 decimal place is 1.7

Round off :

9.638, correct to 2 decimal places

Answer

The given number is 9.638

This number up to 2 decimal places is 9.63

The third decimal place is 8 > 5

So, we increase the 2nd decimal place by 1.

∴ The number correct to 2 decimal places is 9.64

Round off :

0.047, correct to 2 decimal places

Answer

The given number is 0.047

This number up to 2 decimal places is 0.04

The third decimal place is 7 > 5

So, we increase the 2nd decimal place by 1.

∴ The number correct to 2 decimal places is 0.05

Write the value of :

7.451 to the nearest hundredths

Answer

The given number is 7.451

Up to hundredths place it is 7.45. The next place is 1 < 5

∴ The required number is 7.45

Write the value of :

3.157 to the nearest tenths

Answer

The given number is 3.157

Up to tenths place it is 3.1. The next place is 5.

So, we increase the tenths place by 1.

∴ The required number is 3.2

Write the value of :

0.6428 to the nearest thousandths

Answer

The given number is 0.6428

Up to thousandths place it is 0.642. The next place is 8 > 5

So, we increase the thousandths place by 1.

∴ The required number is 0.643

Write the value of :

0.061 to the nearest tenths

Answer

The given number is 0.061

Up to tenths place it is 0.0. The next place is 6 > 5

So, we increase the tenths place by 1.

∴ The required number is 0.1

Write the value of :

0.136 to the nearest hundredths

Answer

The given number is 0.136

Up to hundredths place it is 0.13. The next place is 6 > 5

So, we increase the hundredths place by 1.

∴ The required number is 0.14

Express $\dfrac{6}{7}$ as a decimal, correct to 2 decimal places.

Answer

By actual division, we get:

$\begin{array}{r} 0.857... \\ 7 \overline{\smash{)} 6.000 } \\ \underline{56} \phantom{.00} \\ 40 \phantom{.0} \\ \underline{35} \phantom{.0} \\ 50 \phantom{} \\ \underline{49} \phantom{} \\ 1 \phantom{} \end{array}$

The given number up to 2 decimal places is 0.85

The third decimal place is 7 > 5

So, we increase the 2nd decimal place by 1.

∴ $\dfrac{6}{7}$ correct to 2 decimal places is 0.86