By clue 1, the two numbers in the 2nd row of Number Pyramid 11 sum
to 14, so that the possible lefttoright combinations are 95, 86, 68,
and 59. Since the leftmost numbers in the four rows sum to 11 (clue 4),
9 can't be leftmost in row 2 because the other three numbers would sum
to 2. If 8 were the leftmost number in row 2, the other three leftmost
numbers would add to 3 (4) and would have to be 0, 1, and 2, in some order.
However, 1 and 2 would then be in different rows of the pyramidno (6).
If 59 were the leftright pair in row 2, the other three leftmost numbers
would sum to 6 (4) and would have to be 1, 2, and 3 in some order or
0, 2, and 4 in some order. The numbers can't be 1, 2, and 3 in some order,
since 1 and 2 are in the same row (6). If the numbers were 0, 2, and 4,
since 0 isn't at the apex of the pyramid (2) and since 2 is in the same row
as 1 (6) and thus couldn't be at the apex, 4 would be at the apex of the
pyramid. However, the rightmost number in row 4 would be 5 (7)impossible,
since 5 would be the leftmost number in row 2. Therefore, 6 and then 8 are
in row 2 of Number Pyramid 11. The other three leftmost letters
then add to 5 (4) and must be 0, 1, and 4 in some order or 0, 2, and 3 in
some order. If the numbers were 0, 2, and 3, since 0 isn't at the apex of
the pyramid (2) and since 2 is in the same row as 1 (6) and thus couldn't
be at the apex, 3 would be at the apex of the pyramid. If 2 were the
leftmost number in row 3 and 0 leftmost in row 4, 1 would be next to 0
(3)a contradiction with 6. If 0 were the leftmost number in row 3 and
2 leftmost in row 4, 3 would be next to 2impossible, since 3 would be
at the pyramid apex. So, the other three leftmost letters are 0, 1, and 4
in some order. Since 0 isn't at the apex of the pyramid (2) and since 1
is in the same row as 2 (6) and thus couldn't be at the apex, 4 is at the
apex of the pyramid. If 1 were the leftmost number in row 3 and 0 leftmost
in row 4, 1 would also be next to 0 (3). 0 is the leftmost number in row 3
and 1 leftmost in row 4. By clue 7, the rightmost number in row 4 is 5.
2 is to 1's immediate right in row 4 (3). With the remaining three numbers
being 3, 7, and 9, the only way for clue 5 to work is for 7 to be in the
middle of row 3 with 9 to its right. 3 is in row 4 between 2 and 5.
In sum, Number Pyramid 11 is filled as follows:


