Answer :
Solving puzzles is a way of improving the ability to solve problems
The riddle solution is; IT WAS A SAPPY ONE
The above solution to the riddle is correct due to the following reason:
Question: The parts of the question missing involves solving a equations with the result giving the values of the letters required to solve the puzzle;
1) m + 7 = 9
∴ m = 2
2) x + 11 = 4
∴ x = 7
3) n - 3/5 = 2/5
∴ n = 1
4) -18 = r - 12
∴ r = -6
5) s - (-10) = 2
∴ s = -8
6) 6.3 = b - 1.5
∴ b = 7.8
7) 1.4·h = 5.6
∴ h = 4
8) y ÷ 9 = -3
∴ y = -27
9) -7·c = -63
∴ c = 9
10) x/8 = -3
∴ x = -24
11) (-6/7)·a = 18
∴ a = -21
12) -144·π = -12·π·k
∴ k = 12
Part B;
The length of a banner is 2 and a half times its width
The length of the banner is 20 ft.
Therefore, the width is 8 ft.
Part C
27 out of the 32 members in are decorating for a dance
∴ 5 members are not decorating
Listing the the letters to which the above values point to in the matrix from the puzzle question gives;
ITWASASAPPYONE, which reads;
IT WAS A SAPPY ONE
Learn more about puzzles and algebraic equations here:
https://brainly.com/question/14298523