Finding the Fourth Proportional to 71,987.60, 99,300.12 and 56,046.80

Step by Step Solution

1. Step 1: Write the proportion equation
   71,987.60 : 99,300.12 = 56,046.80 : x
2. Step 2: Convert to fraction form
   71,987.60/99,300.12 = 56,046.80/x
3. Step 3: Cross multiply
   71,987.60x = 99,300.12 × 56,046.80
4. Step 4: Simplify right side
   71,987.60x = 5,565,453,965.62
5. Step 5: Solve for x
   x = 5,565,453,965.62/71,987.60
6. Step 6: Final answer
   x = 77,311.29