Finding the Fourth Proportional to 128,749, 177,659.22 and 72,152.20

Step by Step Solution

1. Step 1: Write the proportion equation
   128,749 : 177,659.22 = 72,152.20 : x
2. Step 2: Convert to fraction form
   128,749/177,659.22 = 72,152.20/x
3. Step 3: Cross multiply
   128,749x = 177,659.22 × 72,152.20
4. Step 4: Simplify right side
   128,749x = 12,818,503,573.28
5. Step 5: Solve for x
   x = 12,818,503,573.28/128,749
6. Step 6: Final answer
   x = 99,561.97