APLA - Vref gusting winds calculation

[flying67]

Hi everyone,

Just a question about APLA and calculating Vref speeds. Am I correct in saying that you would calculate the approach speed by adding half the wind speed + half the gust + Vref = approach speed? I found it didn't work for the question below as I'm getting an answer of 150kts and the answers are showing 152kts

1. You are flying a B727 and decide to calculate your VREF speed given the followinginformation: Approach Speed (1.3Vs): 139kts
   
   Wind Speed: 18kts/ gusting 22kts.
   
   Any help would be appreciated!