Finding the Third Proportional to 122,958 and 290,142

Step by Step Solution

1. Step 1: Write the proportion equation
   122,958 : 290,142 = 290,142 : x
2. Step 2: Convert to fraction form
   122,958/290,142 = 290,142/x
3. Step 3: Cross multiply
   122,958x = 290,142 × 290,142
4. Step 4: Simplify right side
   122,958x = 84,182,380,164
5. Step 5: Solve for x
   x = 84,182,380,164/122,958
6. Step 6: Final answer
   x = 684,643.38