Finding the Fourth Proportional to 139,980.48, 209,763.28 and 115,196.64

Step by Step Solution

1. Step 1: Write the proportion equation
   139,980.48 : 209,763.28 = 115,196.64 : x
2. Step 2: Convert to fraction form
   139,980.48/209,763.28 = 115,196.64/x
3. Step 3: Cross multiply
   139,980.48x = 209,763.28 × 115,196.64
4. Step 4: Simplify right side
   139,980.48x = 24,164,025,051.38
5. Step 5: Solve for x
   x = 24,164,025,051.38/139,980.48
6. Step 6: Final answer
   x = 172,624.25