Find the number a, if(i) 8.4% of a is 42(ii) 0.5 of a is 3(iii) of a i

1.	Find the number a, if(i) 8.4% of a is 42(ii) 0.5 of a is 3(iii) of a is 50(iv) 100% of a is 100
Answer» (i) 8.4% of a is 42 \(=\frac{(a\times8.4)}{100}\)=42 = a =\(\frac{42\times100}{8.4}=\)\(=\frac{42\times100\times10}{84}\)=500 (ii) 0.5 of a is 3 \(=\frac{a\times0.5}{100}\)=3 \(=a=\frac{3\times100}{0.5}=\frac{3\times100\times10}{5}\)=600 (iii) \(\frac{1}{2}\)of a is 50 \(({a}\times\frac{1}{2})\)=50 = a = \({50\times2}\)= 100 (iv) 100% of a is 100 \(=\frac{a\times100}{100}\) =100 = a =\(\frac{100\times100}{100}\) =100

Find the number a, if(i) 8.4% of a is 42(ii) 0.5 of a is 3(iii) of a is 50(iv) 100% of a is 100

Answer»

(i) 8.4% of a is 42

\(=\frac{(a\times8.4)}{100}\)=42

= a =\(\frac{42\times100}{8.4}=\)\(=\frac{42\times100\times10}{84}\)=500

(ii) 0.5 of a is 3

\(=\frac{a\times0.5}{100}\)=3

\(=a=\frac{3\times100}{0.5}=\frac{3\times100\times10}{5}\)=600

(iii) \(\frac{1}{2}\)of a is 50

\(({a}\times\frac{1}{2})\)=50

= a = \({50\times2}\)= 100

(iv) 100% of a is 100

\(=\frac{a\times100}{100}\) =100

= a =\(\frac{100\times100}{100}\) =100