Finding the Fourth Proportional to 260,061.20, 390,130.58 and 80,131.58

Step by Step Solution

1. Step 1: Write the proportion equation
   260,061.20 : 390,130.58 = 80,131.58 : x
2. Step 2: Convert to fraction form
   260,061.20/390,130.58 = 80,131.58/x
3. Step 3: Cross multiply
   260,061.20x = 390,130.58 × 80,131.58
4. Step 4: Simplify right side
   260,061.20x = 31,261,779,781.72
5. Step 5: Solve for x
   x = 31,261,779,781.72/260,061.20
6. Step 6: Final answer
   x = 120,209.32