Brain Teasers and Puzzles 

Workings

Hint
Another example, PEN is a complete word because:
   -en = ten
   p-n = pin
   pe- = pea

Answer
Three of the words are not complete: flew, rook, lamp.

Reasoning
The remaining 7 words can be changed as follows:
team:  -eam = beam
 t-am = tram
 te-m = term
 tea- = tear

cost:  -ost = host
 c-st = cast
 co-t = coat
 cos- = cosy

flew:  -lew = blew
 f-ew = ---- *
 fl-w = flow
 fle- = flex

ward:  -ard = card
 w-rd = word
 wa-d = wand
 war- = warm

fail:  -ail = nail
 f-il = foil
 fa-l = fall
 fai- = fair

rook:  -ook = book
 r-ok = ---- *
 ro-k = rock
 roo- = roof

soft:  -oft = loft
 s-ft = sift
 so-t = sort
 sof- = sofa

most:  -ost = cost
 m-st = mast
 mo-t = moat
 mos- = moss

lamp:  -amp = damp
 l-mp = lump
 la-p = ---- *
 lam- = lamb

load:  -oad = road
 l-ad = lead
 lo-d = loud
 loa- = loaf

Workings

Hint
# is worth 3.

Answer
14.

Reasoning
The values are: @ = 7, & = 4, $ = 8, # = 3, % = 5.

But...

...you don't have to find the value of every symbol!

The rows add up to 80, which means that the columns must also add up to 80.

24 + ? + 17 + 25 = 80.

? = 14.

Workings

Hint
The country spans mode than one word.

Answer
Finland.

After many years studying in the field of astrophysics, the bofFIN LANDed a plum job with the National Space Agency, where he became a leading figure in the area of quasars.

Workings

Hint
These are all Greek letters.

Answer
θ (theta).

Reasoning
These are all Greek letters, and they are:

   xi, chi, theta, psi, pi, phi

They all sound similar to each other, except θ.