Finding the Third Proportional to 678.38 and 1,261.83

Step by Step Solution

1. Step 1: Write the proportion equation
   678.38 : 1,261.83 = 1,261.83 : x
2. Step 2: Convert to fraction form
   678.38/1,261.83 = 1,261.83/x
3. Step 3: Cross multiply
   678.38x = 1,261.83 × 1,261.83
4. Step 4: Simplify right side
   678.38x = 1,592,210.22
5. Step 5: Solve for x
   x = 1,592,210.22/678.38
6. Step 6: Final answer
   x = 2,347.09