Finding the Fourth Proportional to 2,609.56, 3,914.56 and 853.88

Step by Step Solution

1. Step 1: Write the proportion equation
   2,609.56 : 3,914.56 = 853.88 : x
2. Step 2: Convert to fraction form
   2,609.56/3,914.56 = 853.88/x
3. Step 3: Cross multiply
   2,609.56x = 3,914.56 × 853.88
4. Step 4: Simplify right side
   2,609.56x = 3,342,564.49
5. Step 5: Solve for x
   x = 3,342,564.49/2,609.56
6. Step 6: Final answer
   x = 1,280.89