Finding the Fourth Proportional to 21,856.70, 32,778.65 and 8,526.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,856.70 : 32,778.65 = 8,526.72 : x
2. Step 2: Convert to fraction form
   21,856.70/32,778.65 = 8,526.72/x
3. Step 3: Cross multiply
   21,856.70x = 32,778.65 × 8,526.72
4. Step 4: Simplify right side
   21,856.70x = 279,494,327.89
5. Step 5: Solve for x
   x = 279,494,327.89/21,856.70
6. Step 6: Final answer
   x = 12,787.58