Finding the Fourth Proportional to 128,641.50, 177,525.27 and 72,054.09

Step by Step Solution

1. Step 1: Write the proportion equation
   128,641.50 : 177,525.27 = 72,054.09 : x
2. Step 2: Convert to fraction form
   128,641.50/177,525.27 = 72,054.09/x
3. Step 3: Cross multiply
   128,641.50x = 177,525.27 × 72,054.09
4. Step 4: Simplify right side
   128,641.50x = 12,791,421,781.85
5. Step 5: Solve for x
   x = 12,791,421,781.85/128,641.50
6. Step 6: Final answer
   x = 99,434.64