You are correct, but you needn't worry about the signs so much. Just remember that the negative sign is used to denote a loss of energy; since the water is hotter, it will be losing energy (-Q) and the iron will gain energy (Q). Now, we substitute the values:
-149.3 * 4.184 * (T - 95) = 412 * 0.44 * (T - 5)
Solving this equation for T,
T = 74.8 °C
<u>Answer:</u> The molality of solution is 0.740 m.
<u>Explanation:</u>
To calculate the mass of solvent (water), we use the equation:

Volume of water = 750 mL
Density of water = 1 g/mL
Putting values in above equation, we get:

To calculate the molality of solution, we use the equation:

Where,
= Given mass of solute
= 100.0 g
= Molar mass of solute
= 180 g/mol
= Mass of solvent (water) = 750 g
Putting values in above equation, we get:

Hence, the molality of solution is 0.740 m.
1/15 is the correct answer I think