Finding the Third Proportional to 216,604 and 521,820

Step by Step Solution

1. Step 1: Write the proportion equation
   216,604 : 521,820 = 521,820 : x
2. Step 2: Convert to fraction form
   216,604/521,820 = 521,820/x
3. Step 3: Cross multiply
   216,604x = 521,820 × 521,820
4. Step 4: Simplify right side
   216,604x = 272,296,112,400
5. Step 5: Solve for x
   x = 272,296,112,400/216,604
6. Step 6: Final answer
   x = 1,257,114.88