Finding the Fourth Proportional to 1,451.10, 2,002.56 and 821.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,451.10 : 2,002.56 = 821.61 : x
2. Step 2: Convert to fraction form
   1,451.10/2,002.56 = 821.61/x
3. Step 3: Cross multiply
   1,451.10x = 2,002.56 × 821.61
4. Step 4: Simplify right side
   1,451.10x = 1,645,326.27
5. Step 5: Solve for x
   x = 1,645,326.27/1,451.10
6. Step 6: Final answer
   x = 1,133.85