Finding the Third Proportional to 781.31 and 1,693.69

Step by Step Solution

1. Step 1: Write the proportion equation
   781.31 : 1,693.69 = 1,693.69 : x
2. Step 2: Convert to fraction form
   781.31/1,693.69 = 1,693.69/x
3. Step 3: Cross multiply
   781.31x = 1,693.69 × 1,693.69
4. Step 4: Simplify right side
   781.31x = 2,868,577.35
5. Step 5: Solve for x
   x = 2,868,577.35/781.31
6. Step 6: Final answer
   x = 3,671.49