Finding the Fourth Proportional to 209,556.57, 314,199.54 and 89,691.78

Step by Step Solution

1. Step 1: Write the proportion equation
   209,556.57 : 314,199.54 = 89,691.78 : x
2. Step 2: Convert to fraction form
   209,556.57/314,199.54 = 89,691.78/x
3. Step 3: Cross multiply
   209,556.57x = 314,199.54 × 89,691.78
4. Step 4: Simplify right side
   209,556.57x = 28,181,116,017.78
5. Step 5: Solve for x
   x = 28,181,116,017.78/209,556.57
6. Step 6: Final answer
   x = 134,479.75