Finding the Fourth Proportional to 1,406.72, 2,111.19 and 790.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,406.72 : 2,111.19 = 790.31 : x
2. Step 2: Convert to fraction form
   1,406.72/2,111.19 = 790.31/x
3. Step 3: Cross multiply
   1,406.72x = 2,111.19 × 790.31
4. Step 4: Simplify right side
   1,406.72x = 1,668,494.57
5. Step 5: Solve for x
   x = 1,668,494.57/1,406.72
6. Step 6: Final answer
   x = 1,186.09