Finding the Fourth Proportional to 1,379.93, 1,904.28 and 790.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.93 : 1,904.28 = 790.46 : x
2. Step 2: Convert to fraction form
   1,379.93/1,904.28 = 790.46/x
3. Step 3: Cross multiply
   1,379.93x = 1,904.28 × 790.46
4. Step 4: Simplify right side
   1,379.93x = 1,505,247.65
5. Step 5: Solve for x
   x = 1,505,247.65/1,379.93
6. Step 6: Final answer
   x = 1,090.82