Finding the Fourth Proportional to 1,559.60, 2,338.72 and 856.35

Step by Step Solution

1. Step 1: Write the proportion equation
   1,559.60 : 2,338.72 = 856.35 : x
2. Step 2: Convert to fraction form
   1,559.60/2,338.72 = 856.35/x
3. Step 3: Cross multiply
   1,559.60x = 2,338.72 × 856.35
4. Step 4: Simplify right side
   1,559.60x = 2,002,758.97
5. Step 5: Solve for x
   x = 2,002,758.97/1,559.60
6. Step 6: Final answer
   x = 1,284.15