Finding the Third Proportional to 31,439 and 63,790

Step by Step Solution

1. Step 1: Write the proportion equation
   31,439 : 63,790 = 63,790 : x
2. Step 2: Convert to fraction form
   31,439/63,790 = 63,790/x
3. Step 3: Cross multiply
   31,439x = 63,790 × 63,790
4. Step 4: Simplify right side
   31,439x = 4,069,164,100
5. Step 5: Solve for x
   x = 4,069,164,100/31,439
6. Step 6: Final answer
   x = 129,430.46