You may have incorrectly converted 2,400 pounds to tons by moving the decimal point 3 places to the left, and then subtracted 2.4 from 3. You must multiply the number of pounds by $\displaystyle\frac{{{1}\ \text{ ton}}}{{{2},{000}\ \text{ pounds}}}\usepackage{cmbright}\Huge\$ if you want to convert from pounds to tons. The correct answer is 3,600 pounds.