4.2% is equivalent to what fraction in reduced terms

1. Given 4.2%, convert it to a fraction:
\frac{4.2}{100}

2. Eliminate the decimal by multiplying the numerator and the denominator by 10:
\frac{4.2 \times 10}{100 \times 10} = \frac{42}{1000}

3. Find the GCD of 42 and 1000, which is 2.

4. Divide both the numerator and the denominator by the GCD:
\frac{42 \div 2}{1000 \div 2} = \frac{21}{500}

5. Therefore, the simplest fractional form of 4.2% is:
\frac{21}{500}