Finding the Fourth Proportional to 1,379.25, 1,903.59 and 819.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.25 : 1,903.59 = 819.81 : x
2. Step 2: Convert to fraction form
   1,379.25/1,903.59 = 819.81/x
3. Step 3: Cross multiply
   1,379.25x = 1,903.59 × 819.81
4. Step 4: Simplify right side
   1,379.25x = 1,560,582.12
5. Step 5: Solve for x
   x = 1,560,582.12/1,379.25
6. Step 6: Final answer
   x = 1,131.47