Finding the Fourth Proportional to 1,551.76, 2,326.20 and 820.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,551.76 : 2,326.20 = 820.72 : x
2. Step 2: Convert to fraction form
   1,551.76/2,326.20 = 820.72/x
3. Step 3: Cross multiply
   1,551.76x = 2,326.20 × 820.72
4. Step 4: Simplify right side
   1,551.76x = 1,909,158.86
5. Step 5: Solve for x
   x = 1,909,158.86/1,551.76
6. Step 6: Final answer
   x = 1,230.32