To increase an amount by 12.5% what single multiplier would you use

An airplane is taking off headed due north with an air speed of 173 miles per hour at an angle of 18° relative to the horizontal. the wind is blowing with a velocity of 42 miles per hour at an angle of s47°e. find a vector that represents the resultant velocity of the plane relative to the point of takeoff. let i point east, j point north, and k point up.