To write \( 9.1 \times 10^3 \) in standard form, you simply express it as a number rather than in scientific notation.
Calculating \( 9.1 \times 10^3 \):
\[ 9.1 \times 10^3 = 9.1 \times 1000 = 9100 \]
So, in standard form, \( 9.1 \times 10^3 \) is written as 9100.