Finding the Third Proportional to 638.72 and 1,364.06

Step by Step Solution

1. Step 1: Write the proportion equation
   638.72 : 1,364.06 = 1,364.06 : x
2. Step 2: Convert to fraction form
   638.72/1,364.06 = 1,364.06/x
3. Step 3: Cross multiply
   638.72x = 1,364.06 × 1,364.06
4. Step 4: Simplify right side
   638.72x = 1,860,666.50
5. Step 5: Solve for x
   x = 1,860,666.50/638.72
6. Step 6: Final answer
   x = 2,913.12