Finding the Third Proportional to 291,240 and 636,360

Step by Step Solution

1. Step 1: Write the proportion equation
   291,240 : 636,360 = 636,360 : x
2. Step 2: Convert to fraction form
   291,240/636,360 = 636,360/x
3. Step 3: Cross multiply
   291,240x = 636,360 × 636,360
4. Step 4: Simplify right side
   291,240x = 404,954,049,600
5. Step 5: Solve for x
   x = 404,954,049,600/291,240
6. Step 6: Final answer
   x = 1,390,447.91