Step 1: Put a decimal point at the end of the number: <span><span>64090000000. </span>Step 2: Move the decimal point 10 spaces to the left: </span><span>6.4090000000 </span>Number Part: 6.4090000000 aka 6.409⋅<span>10Exponent Part: 10 Answer: 6.409 x 1010</span>