Finding the Fourth Proportional to 128,751.76, 177,667.60 and 72,152.16

Step by Step Solution

1. Step 1: Write the proportion equation
   128,751.76 : 177,667.60 = 72,152.16 : x
2. Step 2: Convert to fraction form
   128,751.76/177,667.60 = 72,152.16/x
3. Step 3: Cross multiply
   128,751.76x = 177,667.60 × 72,152.16
4. Step 4: Simplify right side
   128,751.76x = 12,819,101,102.02
5. Step 5: Solve for x
   x = 12,819,101,102.02/128,751.76
6. Step 6: Final answer
   x = 99,564.47