Finding the Third Proportional to 406.25 and 870.25

Step by Step Solution

1. Step 1: Write the proportion equation
   406.25 : 870.25 = 870.25 : x
2. Step 2: Convert to fraction form
   406.25/870.25 = 870.25/x
3. Step 3: Cross multiply
   406.25x = 870.25 × 870.25
4. Step 4: Simplify right side
   406.25x = 757,335.06
5. Step 5: Solve for x
   x = 757,335.06/406.25
6. Step 6: Final answer
   x = 1,864.21