Cross Number Puzzle

Have a go at this Cross Number Puzzle created by a boy in Grade 6. I might give some hints and solutions in the "Comments" section, if I can work out the answers myself...

Across

1. When fractions aren't tasty enough

3. You won't find the answer that easily

4. A calculator has to pay the __ __ __ __

5. "Half a lucky number, half an unlucky number, then twice!" - Julius Caesar

8. It's square, prime AND prime x triangle AND ninth power - prime...

10. 5th show on Channel 7 x perfect? Only second grade...

11. Oranges? No, pears...I have 5 (NOT 10)

13. The anti-nine of 29296

14. 10[SHIFT6]2 - 2[SHIFT6]3 less than 10 across

Down

1. It's letters are in order, but its numbers are backwards

2. Cubed, it's 205 x 10[SHIFT6]3 rounded to the nearest 1000

4. A + B + C = 18; A x B x C = 196; ABC = __ __ __

6. Put a 9-sided square with what 4 x 5 chewed to make a perfect match

7.    10[SHIFT6]6 - (mailbax + 1 ion)

                   [LUCKY?]

8. [Dwarves] x [seas] x [sins]

9. Bury 18 and 13 in a square

11. 50% evil

12. The answer according to a colour?

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