Finding the Third Proportional to 823.86 and 1,812.71

Step by Step Solution

1. Step 1: Write the proportion equation
   823.86 : 1,812.71 = 1,812.71 : x
2. Step 2: Convert to fraction form
   823.86/1,812.71 = 1,812.71/x
3. Step 3: Cross multiply
   823.86x = 1,812.71 × 1,812.71
4. Step 4: Simplify right side
   823.86x = 3,285,921.83
5. Step 5: Solve for x
   x = 3,285,921.83/823.86
6. Step 6: Final answer
   x = 3,988.43