Finding the Third Proportional to 1,216.50 and 2,638.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,216.50 : 2,638.50 = 2,638.50 : x
2. Step 2: Convert to fraction form
   1,216.50/2,638.50 = 2,638.50/x
3. Step 3: Cross multiply
   1,216.50x = 2,638.50 × 2,638.50
4. Step 4: Simplify right side
   1,216.50x = 6,961,682.25
5. Step 5: Solve for x
   x = 6,961,682.25/1,216.50
6. Step 6: Final answer
   x = 5,722.71