Finding the Fourth Proportional to 128,995.56, 178,004.12 and 72,396

Step by Step Solution

1. Step 1: Write the proportion equation
   128,995.56 : 178,004.12 = 72,396 : x
2. Step 2: Convert to fraction form
   128,995.56/178,004.12 = 72,396/x
3. Step 3: Cross multiply
   128,995.56x = 178,004.12 × 72,396
4. Step 4: Simplify right side
   128,995.56x = 12,886,785,909.54
5. Step 5: Solve for x
   x = 12,886,785,909.54/128,995.56
6. Step 6: Final answer
   x = 99,901.00