Finding the Fourth Proportional to 1,353.60, 1,868.33 and 856.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,353.60 : 1,868.33 = 856.40 : x
2. Step 2: Convert to fraction form
   1,353.60/1,868.33 = 856.40/x
3. Step 3: Cross multiply
   1,353.60x = 1,868.33 × 856.40
4. Step 4: Simplify right side
   1,353.60x = 1,600,030.61
5. Step 5: Solve for x
   x = 1,600,030.61/1,353.60
6. Step 6: Final answer
   x = 1,182.06