Its not that hard.
Half of the inch part is 1/2 inch which is also 4/8.
half of the 3/4 part is 3/8 you get by multiplying the denominator by 2.
Put it all back together and you get the 4/8 part and the 3/8 part so in total its 7/8 of an inch.
Molality is a property of a solution and is defined as the number of moles of solute per kilogram of solvent. The SI unit for molality is mol/kg. A solution with a molality of 3 mol/kg is often described as “3 molal” or “3 m.” However, following the SI system of units, mol/kg or a related SI unit is now preferred.
Units. The SI unit for molality is mol/kg, or moles solute per kg of solvent.