Finding the Third Proportional to 1,242.50 and 1,691.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,242.50 : 1,691.50 = 1,691.50 : x
2. Step 2: Convert to fraction form
   1,242.50/1,691.50 = 1,691.50/x
3. Step 3: Cross multiply
   1,242.50x = 1,691.50 × 1,691.50
4. Step 4: Simplify right side
   1,242.50x = 2,861,172.25
5. Step 5: Solve for x
   x = 2,861,172.25/1,242.50
6. Step 6: Final answer
   x = 2,302.75