Finding the Third Proportional to 917,864 and 1,290,272

Step by Step Solution

1. Step 1: Write the proportion equation
   917,864 : 1,290,272 = 1,290,272 : x
2. Step 2: Convert to fraction form
   917,864/1,290,272 = 1,290,272/x
3. Step 3: Cross multiply
   917,864x = 1,290,272 × 1,290,272
4. Step 4: Simplify right side
   917,864x = 1,664,801,833,984
5. Step 5: Solve for x
   x = 1,664,801,833,984/917,864
6. Step 6: Final answer
   x = 1,813,778.33