Finding the Fourth Proportional to 1,379.48, 1,903.72 and 790.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.48 : 1,903.72 = 790.10 : x
2. Step 2: Convert to fraction form
   1,379.48/1,903.72 = 790.10/x
3. Step 3: Cross multiply
   1,379.48x = 1,903.72 × 790.10
4. Step 4: Simplify right side
   1,379.48x = 1,504,129.17
5. Step 5: Solve for x
   x = 1,504,129.17/1,379.48
6. Step 6: Final answer
   x = 1,090.36