Finding the Third Proportional to 187.31 and 287.72

Step by Step Solution

1. Step 1: Write the proportion equation
   187.31 : 287.72 = 287.72 : x
2. Step 2: Convert to fraction form
   187.31/287.72 = 287.72/x
3. Step 3: Cross multiply
   187.31x = 287.72 × 287.72
4. Step 4: Simplify right side
   187.31x = 82,782.08
5. Step 5: Solve for x
   x = 82,782.08/187.31
6. Step 6: Final answer
   x = 441.95