Finding the Fourth Proportional to 139,422.06, 208,961.78 and 64,440.77

Step by Step Solution

1. Step 1: Write the proportion equation
   139,422.06 : 208,961.78 = 64,440.77 : x
2. Step 2: Convert to fraction form
   139,422.06/208,961.78 = 64,440.77/x
3. Step 3: Cross multiply
   139,422.06x = 208,961.78 × 64,440.77
4. Step 4: Simplify right side
   139,422.06x = 13,465,656,636.76
5. Step 5: Solve for x
   x = 13,465,656,636.76/139,422.06
6. Step 6: Final answer
   x = 96,581.97