Finding the Third Proportional to 1,216.69 and 1,383.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,216.69 : 1,383.75 = 1,383.75 : x
2. Step 2: Convert to fraction form
   1,216.69/1,383.75 = 1,383.75/x
3. Step 3: Cross multiply
   1,216.69x = 1,383.75 × 1,383.75
4. Step 4: Simplify right side
   1,216.69x = 1,914,764.06
5. Step 5: Solve for x
   x = 1,914,764.06/1,216.69
6. Step 6: Final answer
   x = 1,573.75