Complete the Decimal Expression: 2.4 = ?

While $\frac{4}{10}$ does equal 0.4, you have the wrong whole number! The decimal 2.4 has a whole number part of 2, not 1. Plus, $\frac{4}{10}$ should be simplified to $\frac{2}{5}$.

Always simplify! Find the GCD (Greatest Common Divisor) of the numerator and denominator. For $\frac{4}{10}$, the GCD is 2, so divide both parts by 2 to get $\frac{2}{5}$.

The same process works! Two decimal places = hundredths, three = thousandths, etc. For example: $3.25 = 3\frac{25}{100} = 3\frac{1}{4}$ after simplifying.

Convert it back to a decimal! Divide the fraction part and add to the whole number. For $2\frac{2}{5}$: 2 ÷ 5 = 0.4, so 2 + 0.4 = 2.4 ✓

Mixed numbers show the exact value without rounding! They're especially useful in cooking, construction, and when working with fractions in algebra. Both forms are valuable!