Finding the Fourth Proportional to 1,353.09, 1,867.50 and 855.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,353.09 : 1,867.50 = 855.57 : x
2. Step 2: Convert to fraction form
   1,353.09/1,867.50 = 855.57/x
3. Step 3: Cross multiply
   1,353.09x = 1,867.50 × 855.57
4. Step 4: Simplify right side
   1,353.09x = 1,597,776.98
5. Step 5: Solve for x
   x = 1,597,776.98/1,353.09
6. Step 6: Final answer
   x = 1,180.84