Finding the Third Proportional to 1,239.50 and 2,672.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,239.50 : 2,672.50 = 2,672.50 : x
2. Step 2: Convert to fraction form
   1,239.50/2,672.50 = 2,672.50/x
3. Step 3: Cross multiply
   1,239.50x = 2,672.50 × 2,672.50
4. Step 4: Simplify right side
   1,239.50x = 7,142,256.25
5. Step 5: Solve for x
   x = 7,142,256.25/1,239.50
6. Step 6: Final answer
   x = 5,762.21