Finding the Fourth Proportional to 128,643, 177,527.34 and 72,054.24

Step by Step Solution

1. Step 1: Write the proportion equation
   128,643 : 177,527.34 = 72,054.24 : x
2. Step 2: Convert to fraction form
   128,643/177,527.34 = 72,054.24/x
3. Step 3: Cross multiply
   128,643x = 177,527.34 × 72,054.24
4. Step 4: Simplify right side
   128,643x = 12,791,597,562.92
5. Step 5: Solve for x
   x = 12,791,597,562.92/128,643
6. Step 6: Final answer
   x = 99,434.85