Finding the Third Proportional to 609.50 and 915.50

Step by Step Solution

1. Step 1: Write the proportion equation
   609.50 : 915.50 = 915.50 : x
2. Step 2: Convert to fraction form
   609.50/915.50 = 915.50/x
3. Step 3: Cross multiply
   609.50x = 915.50 × 915.50
4. Step 4: Simplify right side
   609.50x = 838,140.25
5. Step 5: Solve for x
   x = 838,140.25/609.50
6. Step 6: Final answer
   x = 1,375.13