Finding the Third Proportional to 858.38 and 1,123.31

Step by Step Solution

1. Step 1: Write the proportion equation
   858.38 : 1,123.31 = 1,123.31 : x
2. Step 2: Convert to fraction form
   858.38/1,123.31 = 1,123.31/x
3. Step 3: Cross multiply
   858.38x = 1,123.31 × 1,123.31
4. Step 4: Simplify right side
   858.38x = 1,261,830.97
5. Step 5: Solve for x
   x = 1,261,830.97/858.38
6. Step 6: Final answer
   x = 1,470.02