Finding the Third Proportional to 99.28 and 206.16

Step by Step Solution

1. Step 1: Write the proportion equation
   99.28 : 206.16 = 206.16 : x
2. Step 2: Convert to fraction form
   99.28/206.16 = 206.16/x
3. Step 3: Cross multiply
   99.28x = 206.16 × 206.16
4. Step 4: Simplify right side
   99.28x = 42,500.40
5. Step 5: Solve for x
   x = 42,500.40/99.28
6. Step 6: Final answer
   x = 428.08