Finding the Fourth Proportional to 1,379.68, 1,903.98 and 820.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.68 : 1,903.98 = 820.46 : x
2. Step 2: Convert to fraction form
   1,379.68/1,903.98 = 820.46/x
3. Step 3: Cross multiply
   1,379.68x = 1,903.98 × 820.46
4. Step 4: Simplify right side
   1,379.68x = 1,562,139.43
5. Step 5: Solve for x
   x = 1,562,139.43/1,379.68
6. Step 6: Final answer
   x = 1,132.25