Finding the Third Proportional to 291,231 and 636,342

Step by Step Solution

1. Step 1: Write the proportion equation
   291,231 : 636,342 = 636,342 : x
2. Step 2: Convert to fraction form
   291,231/636,342 = 636,342/x
3. Step 3: Cross multiply
   291,231x = 636,342 × 636,342
4. Step 4: Simplify right side
   291,231x = 404,931,140,964
5. Step 5: Solve for x
   x = 404,931,140,964/291,231
6. Step 6: Final answer
   x = 1,390,412.22