Find:
$(i).\ 7 \div 3.5$
$(ii).\ 36 \div 0.2$
$(iii).\ 3.25 \div 0.5$
$(iv).\ 30.94 \div 0.7$
$(v).\ 0.5 \div 0.25$
$(vi).\ 7.75 \div 0.25$
$(vii).\ 76.5 \div 0.15$
$(viii).\ 37.8 \div 1.4$
$(ix).\ 2.73 \div 1.3$

AcademicMathematicsNCERTClass 7

To do:

We have to find

(i) $7 \div 3.5$

(ii) $36 \div 0.2$

(iii) $3.25 \div 0.5$

(iv) $30.94 \div 0.7$

(v) $0.5 \div 0.25$

(vi) $7.75 \div 0.25$

(vii) $76.5 \div 0.15$

(viii) $37.8 \div 1.4$

(ix) $2.73 \div 1.3$

Solution:

We know that,

On dividing a decimal by $10^n$, the decimal point shifts to the left by $n$ places.

$\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c}$

Therefore,

(i) $7 \div3.5=7\times\frac{1}{3.5}$

$=7\times\frac{10}{35}$

$=\frac{70}{35}$

$=\frac{2}{1}$

$=2$

(ii) $36 \div0.2=36\times\frac{1}{0.2}$

$=36\times\frac{10}{2}$

$=\frac{360}{2}$

$=180$

(iii) $3.25 \div0.5=3.25\times\frac{1}{0.5}$

$=3.25\times\frac{10}{5}$

$=3.25\times2$

$=6.5$

(iv) $30.94 \div0.7=\frac{3094}{100}\times\frac{1}{0.7}$

$=\frac{3094}{100}\times\frac{10}{7}$

$=\frac{3094}{70}$

$=44.2$

(v) $0.5 \div0.25=\frac{5}{10}\times\frac{1}{0.25}$

$=\frac{5}{10}\times\frac{100}{25}$

$=\frac{50}{25}$

$=2$

(vi) $7.75\div0.25=\frac{775}{100} \times \frac{1}{0.25}$

$=\frac{775}{100}\times\frac{100}{25}$

$=\frac{775}{25}$

$=31$

(vii) $76.5 \div0.15=76.5\times\frac{1}{0.15}$

$=\frac{7650}{15}$

$=510$

(viii) $37.8 \div1.4=37.8\times\frac{1}{1.4}$

$=\frac{378}{10}\times\frac{10}{14}$

$=\frac{378}{14}$

$=27$

(ix) $2.73 \div1.3=\frac{273}{100}\times\frac{10}{13}$

$=\frac{21}{10}$

$=2.1$

raja
Updated on 10-Oct-2022 13:32:37

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