Medium Puzzles 

Workings

Hint
Draw a grid of the two colours each gardener could have.

Answer
Name
   Rose1
      Rose2

Gardener Blue
   red
      green

Gardener Green
   yellow
      red

Gardener Red
   blue
      yellow

Gardener Yellow
   blue
      green

Reasoning
We can create a grid of the possible flowers each person could have. Initially, they each have the possibility of BGRY (blue, green, red, yellow) and as we work our way through the clues we can eliminate certain options.
Person  F1     F2
Blue    BGRY   BGRY
Green   BGRY   BGRY
Red     BGRY   BGRY
Yellow  BGRY   BGRY

From (1), (2), (3) and (4) we can reduce the options to:

Blue    BGR BGR
Green   Y   BGRY
Red     B   BRY
Yellow  BGY BGY

By (9) this becomes:

Blue    BGR BGR
Green   Y   BGR
Red     B   RY
Yellow  BGY BGY

By (8) we get:

Blue    BGR BGR
Green   Y   BR
Red     B   RY
Yellow  BGY BGY

Only Blue can satisfy (5), and Yellow is the only person who can have the other G.

Blue    R G
Green   Y BR
Red     B RY
Yellow  G BY

By (8), Yellow can't be Y.

Blue    R G
Green   Y BR
Red     B RY
Yellow  G B

Since there are only two of each colour, we can reduce further:

Blue    R G
Green   Y R
Red     B Y
Yellow  G B

Workings

Hint
The chemical symbol for iron is Fe.

Answer
Yttrium.

From the atomic element's symbols which are spelling February: Fe + Br + U + Ar + Y.

Workings

Hint
There are three animals.

Answer
There are currently 6 different answers, can you find another?

Zebra, guitar, quick, way, box, vowel, monkey, eel, raj, package, sill, moon, heap, deep, fun.

Zebra, guitar, quick, say, box, vowed, monkey, eel, raj, package, hill, moon, leap, weep, fun.

Zebra, guitar, quick, sad, box, vowel, monkey, eel, ray, package, will, moon, heap, jeep, fun.

Zebra, guitar, quick, jam, box, vowel, donkey, eel, ray, package, will, moon, heap, seep, fun.

Zebra, guitar, quick, jaw, box, vowel, monkey, eel, ray, package, fill, moon, heap, deep, sun.

Zebra, guitar, quick, lay, box, vowed, monkey, eel, ran, package, will, mojo, heap, seep, fun.

Workings

Hint
The first digit in each row is even, so the first column can only be 2 + 8, 4 + 6, 4 + 8, 6 + 8 (either way around, and it must be a total over 9).

Answer
423 + 675 = 1098.

Reasoning
Remembering that:
   even + even = even
   odd  + odd  = even
   even + odd  = odd

To discuss individual letters, it's easiest to represent the sum as:
   A B C
   D E F +
————————
 G H I J

A and D are both even, and can only be 2 + 8, 4 + 6, 4 + 8, 6 + 8 (either way around, and it must be a total over 9), so the carry can only be 1, so G = 1.

Since column 2 is even + odd = odd, there can be no carry from column 1 (since even + odd + 1 is always even). Therefore, neither C nor F (both odd) can be 7 or 9 (otherwise there would be a carry), so C and F are 3 and 5 (but we don't yet know which is which), therefore J = 8.

Because A + D is even there can't be a carry from column 2, therefore E can't be 9 as this would force a carry. Therefore, I = 9. So, B can't be 0. Therefore, H = 0.

The last remaining odd number makes E = 7. Making B = 2.

Therefore, A and D are 4 and 6 (but we don't yet know which is which).

Since the top row's digits have to add to 9 the top number must be 423.

This makes the sum 423 + 675 = 1098.