Finding the Third Proportional to 131,278 and 287,980

Step by Step Solution

1. Step 1: Write the proportion equation
   131,278 : 287,980 = 287,980 : x
2. Step 2: Convert to fraction form
   131,278/287,980 = 287,980/x
3. Step 3: Cross multiply
   131,278x = 287,980 × 287,980
4. Step 4: Simplify right side
   131,278x = 82,932,480,400
5. Step 5: Solve for x
   x = 82,932,480,400/131,278
6. Step 6: Final answer
   x = 631,731.75