Finding the Fourth Proportional to 9,102.72, 12,561.71 and 5,123.76

Step by Step Solution

1. Step 1: Write the proportion equation
   9,102.72 : 12,561.71 = 5,123.76 : x
2. Step 2: Convert to fraction form
   9,102.72/12,561.71 = 5,123.76/x
3. Step 3: Cross multiply
   9,102.72x = 12,561.71 × 5,123.76
4. Step 4: Simplify right side
   9,102.72x = 64,363,161.61
5. Step 5: Solve for x
   x = 64,363,161.61/9,102.72
6. Step 6: Final answer
   x = 7,070.76