Finding the Fourth Proportional to 98,878.78, 136,462.50 and 56,443.69

Step by Step Solution

1. Step 1: Write the proportion equation
   98,878.78 : 136,462.50 = 56,443.69 : x
2. Step 2: Convert to fraction form
   98,878.78/136,462.50 = 56,443.69/x
3. Step 3: Cross multiply
   98,878.78x = 136,462.50 × 56,443.69
4. Step 4: Simplify right side
   98,878.78x = 7,702,447,046.63
5. Step 5: Solve for x
   x = 7,702,447,046.63/98,878.78
6. Step 6: Final answer
   x = 77,897.88