Sharper Image 2011 comercial wind problem has me stumped

[whistlerboy02]

It's question 43 on page 190. and should simple but i cant get the correct answer for groundspeed in the climb.
course 250 M
wind 140/20
TAS 120 KTAS

the possible answers are
a) 108
b)132
C)120
D) 150

I am getting 125 everytime and the book is telling me the answer is b)
it wouldnt bug me as much if the 2 follow questions didnt relate.
am i missing something

[Dagwood]

I get 125 as well.

http://www.csgnetwork.com/e6bcalc.html

[straightpilot]

you have a 250-140 = 110 degree crosswind, which has a slight tailwind component, so A and C are wrong. D is not reasonable - you're not going to get a 30 knot push from that near-crosswind - so B is the "best" answer.

No E6B - mechanical or otherwise - was used or abused for this calculation.

[Aeros]

I don't have the book but I do see that you indicated that the course is in Magnetic. Are the wind values you provided also in magnetic? Does applying the variation solve the problem?

[whistlerboy02]

Thanks to you both and straightpilot who dares to actually try a guestimate. A small push could also come up with the 125knot that dagwood and I are stuck on.
I thought my mistake might be in the course. The route is off Salmon Arm and track V323 to Kamloops. So i am pretty sure my ground track of 250 is correct.

[TTJJ]

Your magnetic ground track is correct. V323 is on Radial 250 from YNY to YKA (Kamloops)

The Magnetic Variation here is 20E.
You need to use your true track of 270 to calculate the problem because your winds are given in true, as Aeros stated.

Plugging 270 into your course gives a WCA of -7, a true heading of 263, a magnetic heading of 243 and a ground speed of 132.

Answer B is correct.

(kudos to Aeros)

[whistlerboy02]

OK I can now sleep. I actually tried converting the winds from true to magnetic way back to see if that was the issue and it didnt work... but I left the ground track at 250 and converted the wind direction from 140T to 160M but that made my answer worse...and groundspeed slower. so I figured I was on the wrong track. I guess to convert the winds I should have subtracted the mag variation if i plug in winds from 120 I get 132 also.
Anyway a big thanks guys

[Dagwood]

It would be a good idea to get the "West is best, East is least" thing sorted out before you go flying