Finding the Fourth Proportional to 99,821.30, 137,779.89 and 57,384.50

Step by Step Solution

1. Step 1: Write the proportion equation
   99,821.30 : 137,779.89 = 57,384.50 : x
2. Step 2: Convert to fraction form
   99,821.30/137,779.89 = 57,384.50/x
3. Step 3: Cross multiply
   99,821.30x = 137,779.89 × 57,384.50
4. Step 4: Simplify right side
   99,821.30x = 7,906,430,097.71
5. Step 5: Solve for x
   x = 7,906,430,097.71/99,821.30
6. Step 6: Final answer
   x = 79,205.84