Finding the Fourth Proportional to 99,889.69, 137,964.79 and 79,539.88

Step by Step Solution

1. Step 1: Write the proportion equation
   99,889.69 : 137,964.79 = 79,539.88 : x
2. Step 2: Convert to fraction form
   99,889.69/137,964.79 = 79,539.88/x
3. Step 3: Cross multiply
   99,889.69x = 137,964.79 × 79,539.88
4. Step 4: Simplify right side
   99,889.69x = 10,973,702,840.83
5. Step 5: Solve for x
   x = 10,973,702,840.83/99,889.69
6. Step 6: Final answer
   x = 109,858.21