Division of decimal numbers - II — lesson. Mathematics State Board, Class 7.

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ii) Division of a decimal number by a whole number

Let us learn how to divide the decimal number by a whole number.

i) \(8.4 ÷ 2\)

\(8.4 ÷ 2 =\)

\frac{8.4}{2} = 8.4 \times \frac{1}{2}

. We can write \(8.4\) as

\frac{84}{10}

So,

\frac{84}{10} \times \frac{1}{2} = \frac{84^{42}}{10} \times \frac{1}{2} = \frac{42}{10} = 4. 2

Therefore,

\frac{8.4}{2} = 4.2

In another way, we can divide given expression using the normal division method.

\begin{array}{l} \underline{4.2} \\ 2) 8.4 \\ \underline{8 ↓} \\ 0 4 \\ \underline{4} \\ \underline{0} \end{array}

iii) Division of a decimal number by another decimal number:

i) Find the value of \(30.8 ÷ 0.7\).

The given expression

\frac{30. 8}{0.7}

. We can rewrite it as

\frac{\frac{308}{10}}{\frac{7}{10}} = \frac{308}{10} \times \frac{10}{7}

Let us simplify it.

\frac{308}{10} \times \frac{10}{7} = \frac{308}{7} = 44

Therefore, the value of \(30.8 ÷ 0.7\) is \(44\).

ii) Find the value of \(115.2 ÷ 0.9\).

Similarly, we can rewrite the given expression

\frac{115.2}{0.9}

\frac{\frac{1152}{10}}{\frac{9}{10}} = \frac{1152}{10} \times \frac{10}{9}

\(=\)

\frac{1152}{10} \times \frac{10}{9} = \frac{1152}{9} = 128

Therefore, \(115.2 ÷ 0.9 = 128\).

Did you find an error?

2. Division of decimal numbers - II