Finding the Fourth Proportional to 1,290.17, 1,932.42 and 1,042.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.17 : 1,932.42 = 1,042.31 : x
2. Step 2: Convert to fraction form
   1,290.17/1,932.42 = 1,042.31/x
3. Step 3: Cross multiply
   1,290.17x = 1,932.42 × 1,042.31
4. Step 4: Simplify right side
   1,290.17x = 2,014,180.69
5. Step 5: Solve for x
   x = 2,014,180.69/1,290.17
6. Step 6: Final answer
   x = 1,561.17