Finding the Fourth Proportional to 12,809.90, 17,677.35 and 7,145.19

Step by Step Solution

1. Step 1: Write the proportion equation
   12,809.90 : 17,677.35 = 7,145.19 : x
2. Step 2: Convert to fraction form
   12,809.90/17,677.35 = 7,145.19/x
3. Step 3: Cross multiply
   12,809.90x = 17,677.35 × 7,145.19
4. Step 4: Simplify right side
   12,809.90x = 126,308,024.45
5. Step 5: Solve for x
   x = 126,308,024.45/12,809.90
6. Step 6: Final answer
   x = 9,860.19