Finding the Fourth Proportional to 139,865.63, 209,796.86 and 83,721.42

Step by Step Solution

1. Step 1: Write the proportion equation
   139,865.63 : 209,796.86 = 83,721.42 : x
2. Step 2: Convert to fraction form
   139,865.63/209,796.86 = 83,721.42/x
3. Step 3: Cross multiply
   139,865.63x = 209,796.86 × 83,721.42
4. Step 4: Simplify right side
   139,865.63x = 17,564,490,612.13
5. Step 5: Solve for x
   x = 17,564,490,612.13/139,865.63
6. Step 6: Final answer
   x = 125,581.18