Finding the Fourth Proportional to 9,109.80, 12,123.81 and 9,109.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,109.80 : 12,123.81 = 9,109.80 : x
2. Step 2: Convert to fraction form
   9,109.80/12,123.81 = 9,109.80/x
3. Step 3: Cross multiply
   9,109.80x = 12,123.81 × 9,109.80
4. Step 4: Simplify right side
   9,109.80x = 110,445,484.34
5. Step 5: Solve for x
   x = 110,445,484.34/9,109.80
6. Step 6: Final answer
   x = 12,123.81