To convert the number \(2.4 \times 10^{-4}\) into standard notation, you need to move the decimal point in the number \(2.4\) four places to the left because the exponent is negative.
Starting with \(2.4\):
- Move the decimal point one place to the left: \(0.24\)
- Move it a second place: \(0.024\)
- Move it a third place: \(0.0024\)
- Move it a fourth place: \(0.00024\)
So, \(2.4 \times 10^{-4} = 0.00024\).
Therefore, the value in standard notation is:
\[ 0.00024 \]