Finding the Fourth Proportional to 191,680.88, 287,404.20 and 91,871.60

Step by Step Solution

1. Step 1: Write the proportion equation
   191,680.88 : 287,404.20 = 91,871.60 : x
2. Step 2: Convert to fraction form
   191,680.88/287,404.20 = 91,871.60/x
3. Step 3: Cross multiply
   191,680.88x = 287,404.20 × 91,871.60
4. Step 4: Simplify right side
   191,680.88x = 26,404,283,700.72
5. Step 5: Solve for x
   x = 26,404,283,700.72/191,680.88
6. Step 6: Final answer
   x = 137,751.27