Finding the Fourth Proportional to 1,917.91, 2,646.59 and 1,078.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,917.91 : 2,646.59 = 1,078.70 : x
2. Step 2: Convert to fraction form
   1,917.91/2,646.59 = 1,078.70/x
3. Step 3: Cross multiply
   1,917.91x = 2,646.59 × 1,078.70
4. Step 4: Simplify right side
   1,917.91x = 2,854,871.24
5. Step 5: Solve for x
   x = 2,854,871.24/1,917.91
6. Step 6: Final answer
   x = 1,488.53