Finding the Fourth Proportional to 151.98, 209.72 and 86.50

Step by Step Solution

1. Step 1: Write the proportion equation
   151.98 : 209.72 = 86.50 : x
2. Step 2: Convert to fraction form
   151.98/209.72 = 86.50/x
3. Step 3: Cross multiply
   151.98x = 209.72 × 86.50
4. Step 4: Simplify right side
   151.98x = 18,140.78
5. Step 5: Solve for x
   x = 18,140.78/151.98
6. Step 6: Final answer
   x = 119.36