Finding the Third Proportional to 388.38 and 830.38

Step by Step Solution

1. Step 1: Write the proportion equation
   388.38 : 830.38 = 830.38 : x
2. Step 2: Convert to fraction form
   388.38/830.38 = 830.38/x
3. Step 3: Cross multiply
   388.38x = 830.38 × 830.38
4. Step 4: Simplify right side
   388.38x = 689,522.64
5. Step 5: Solve for x
   x = 689,522.64/388.38
6. Step 6: Final answer
   x = 1,775.40