Finding the Fourth Proportional to 1,380.06, 1,904.52 and 790.44

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.06 : 1,904.52 = 790.44 : x
2. Step 2: Convert to fraction form
   1,380.06/1,904.52 = 790.44/x
3. Step 3: Cross multiply
   1,380.06x = 1,904.52 × 790.44
4. Step 4: Simplify right side
   1,380.06x = 1,505,408.79
5. Step 5: Solve for x
   x = 1,505,408.79/1,380.06
6. Step 6: Final answer
   x = 1,090.83