Finding the Fourth Proportional to 1,379.76, 1,904.09 and 1,081.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.76 : 1,904.09 = 1,081.38 : x
2. Step 2: Convert to fraction form
   1,379.76/1,904.09 = 1,081.38/x
3. Step 3: Cross multiply
   1,379.76x = 1,904.09 × 1,081.38
4. Step 4: Simplify right side
   1,379.76x = 2,059,041.16
5. Step 5: Solve for x
   x = 2,059,041.16/1,379.76
6. Step 6: Final answer
   x = 1,492.32