Finding the Third Proportional to 623,218 and 891,222

Step by Step Solution

1. Step 1: Write the proportion equation
   623,218 : 891,222 = 891,222 : x
2. Step 2: Convert to fraction form
   623,218/891,222 = 891,222/x
3. Step 3: Cross multiply
   623,218x = 891,222 × 891,222
4. Step 4: Simplify right side
   623,218x = 794,276,653,284
5. Step 5: Solve for x
   x = 794,276,653,284/623,218
6. Step 6: Final answer
   x = 1,274,476.43