Finding the Fourth Proportional to 128,774.64, 177,719.96 and 72,196.92

Step by Step Solution

1. Step 1: Write the proportion equation
   128,774.64 : 177,719.96 = 72,196.92 : x
2. Step 2: Convert to fraction form
   128,774.64/177,719.96 = 72,196.92/x
3. Step 3: Cross multiply
   128,774.64x = 177,719.96 × 72,196.92
4. Step 4: Simplify right side
   128,774.64x = 12,830,833,734.52
5. Step 5: Solve for x
   x = 12,830,833,734.52/128,774.64
6. Step 6: Final answer
   x = 99,637.89