Finding the Third Proportional to 931.22 and 1,280.39

Step by Step Solution

1. Step 1: Write the proportion equation
   931.22 : 1,280.39 = 1,280.39 : x
2. Step 2: Convert to fraction form
   931.22/1,280.39 = 1,280.39/x
3. Step 3: Cross multiply
   931.22x = 1,280.39 × 1,280.39
4. Step 4: Simplify right side
   931.22x = 1,639,400.15
5. Step 5: Solve for x
   x = 1,639,400.15/931.22
6. Step 6: Final answer
   x = 1,760.49