Finding the Fourth Proportional to 2,788.47, 4,182.84 and 840.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,788.47 : 4,182.84 = 840.15 : x
2. Step 2: Convert to fraction form
   2,788.47/4,182.84 = 840.15/x
3. Step 3: Cross multiply
   2,788.47x = 4,182.84 × 840.15
4. Step 4: Simplify right side
   2,788.47x = 3,514,213.03
5. Step 5: Solve for x
   x = 3,514,213.03/2,788.47
6. Step 6: Final answer
   x = 1,260.27