Finding the Fourth Proportional to 1,056.53, 1,458.45 and 820.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,056.53 : 1,458.45 = 820.55 : x
2. Step 2: Convert to fraction form
   1,056.53/1,458.45 = 820.55/x
3. Step 3: Cross multiply
   1,056.53x = 1,458.45 × 820.55
4. Step 4: Simplify right side
   1,056.53x = 1,196,723.86
5. Step 5: Solve for x
   x = 1,196,723.86/1,056.53
6. Step 6: Final answer
   x = 1,132.70