Finding the Fourth Proportional to 1,420.31, 1,959.84 and 790.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,420.31 : 1,959.84 = 790.71 : x
2. Step 2: Convert to fraction form
   1,420.31/1,959.84 = 790.71/x
3. Step 3: Cross multiply
   1,420.31x = 1,959.84 × 790.71
4. Step 4: Simplify right side
   1,420.31x = 1,549,665.09
5. Step 5: Solve for x
   x = 1,549,665.09/1,420.31
6. Step 6: Final answer
   x = 1,091.08