Finding the Third Proportional to 1,678.78 and 1,811.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,678.78 : 1,811.81 = 1,811.81 : x
2. Step 2: Convert to fraction form
   1,678.78/1,811.81 = 1,811.81/x
3. Step 3: Cross multiply
   1,678.78x = 1,811.81 × 1,811.81
4. Step 4: Simplify right side
   1,678.78x = 3,282,664.54
5. Step 5: Solve for x
   x = 3,282,664.54/1,678.78
6. Step 6: Final answer
   x = 1,955.39