Finding the Third Proportional to 86.91 and 131.63

Step by Step Solution

1. Step 1: Write the proportion equation
   86.91 : 131.63 = 131.63 : x
2. Step 2: Convert to fraction form
   86.91/131.63 = 131.63/x
3. Step 3: Cross multiply
   86.91x = 131.63 × 131.63
4. Step 4: Simplify right side
   86.91x = 17,325.14
5. Step 5: Solve for x
   x = 17,325.14/86.91
6. Step 6: Final answer
   x = 199.35