Finding the Fourth Proportional to 99,860.72, 137,808.60 and 55,148.72

Step by Step Solution

1. Step 1: Write the proportion equation
   99,860.72 : 137,808.60 = 55,148.72 : x
2. Step 2: Convert to fraction form
   99,860.72/137,808.60 = 55,148.72/x
3. Step 3: Cross multiply
   99,860.72x = 137,808.60 × 55,148.72
4. Step 4: Simplify right side
   99,860.72x = 7,599,967,894.99
5. Step 5: Solve for x
   x = 7,599,967,894.99/99,860.72
6. Step 6: Final answer
   x = 76,105.68