Finding the Third Proportional to 345.94 and 487.69

Step by Step Solution

1. Step 1: Write the proportion equation
   345.94 : 487.69 = 487.69 : x
2. Step 2: Convert to fraction form
   345.94/487.69 = 487.69/x
3. Step 3: Cross multiply
   345.94x = 487.69 × 487.69
4. Step 4: Simplify right side
   345.94x = 237,839.10
5. Step 5: Solve for x
   x = 237,839.10/345.94
6. Step 6: Final answer
   x = 687.52