Finding the Fourth Proportional to 12,188.72, 16,826.28 and 7,714.64

Step by Step Solution

1. Step 1: Write the proportion equation
   12,188.72 : 16,826.28 = 7,714.64 : x
2. Step 2: Convert to fraction form
   12,188.72/16,826.28 = 7,714.64/x
3. Step 3: Cross multiply
   12,188.72x = 16,826.28 × 7,714.64
4. Step 4: Simplify right side
   12,188.72x = 129,808,692.74
5. Step 5: Solve for x
   x = 129,808,692.74/12,188.72
6. Step 6: Final answer
   x = 10,649.90