Correct option is: (1) \(42 \frac{6}{7}\%\)
Let's assume B's income is x.
Since A's income is 30% less than B's income.
A's income = B's income - 30% of B's income
\(= x - \frac{30}{100} \times x\)
\(= x - 0.3x\)
\(= 0.7x\)
Difference = B's income - A's income
= x - 0.7x
= 0.3x
Percentage Increase \(=\frac{\text{Difference}}{ \text{A's Income}} \times 100\%\)
\(= \frac{0.3x}{0.7x} \times 100 \%\)
\(=\frac{3}{7} \times 100\%\)
\(= \frac{300}{7}\%\)
\(= 42 \frac{6}{7} \%\)
