Finding the Third Proportional to 131,386 and 278,456

Step by Step Solution

1. Step 1: Write the proportion equation
   131,386 : 278,456 = 278,456 : x
2. Step 2: Convert to fraction form
   131,386/278,456 = 278,456/x
3. Step 3: Cross multiply
   131,386x = 278,456 × 278,456
4. Step 4: Simplify right side
   131,386x = 77,537,743,936
5. Step 5: Solve for x
   x = 77,537,743,936/131,386
6. Step 6: Final answer
   x = 590,152.25