Finding the Fourth Proportional to 99,051.36, 136,689.72 and 53,728.50

Step by Step Solution

1. Step 1: Write the proportion equation
   99,051.36 : 136,689.72 = 53,728.50 : x
2. Step 2: Convert to fraction form
   99,051.36/136,689.72 = 53,728.50/x
3. Step 3: Cross multiply
   99,051.36x = 136,689.72 × 53,728.50
4. Step 4: Simplify right side
   99,051.36x = 7,344,133,621.02
5. Step 5: Solve for x
   x = 7,344,133,621.02/99,051.36
6. Step 6: Final answer
   x = 74,144.70