Finding the Third Proportional to 1,243 and 1,978.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,243 : 1,978.75 = 1,978.75 : x
2. Step 2: Convert to fraction form
   1,243/1,978.75 = 1,978.75/x
3. Step 3: Cross multiply
   1,243x = 1,978.75 × 1,978.75
4. Step 4: Simplify right side
   1,243x = 3,915,451.56
5. Step 5: Solve for x
   x = 3,915,451.56/1,243
6. Step 6: Final answer
   x = 3,150.00