Finding the Fourth Proportional to 3,909.39, 5,865.71 and 1,312.53

Step by Step Solution

1. Step 1: Write the proportion equation
   3,909.39 : 5,865.71 = 1,312.53 : x
2. Step 2: Convert to fraction form
   3,909.39/5,865.71 = 1,312.53/x
3. Step 3: Cross multiply
   3,909.39x = 5,865.71 × 1,312.53
4. Step 4: Simplify right side
   3,909.39x = 7,698,913.78
5. Step 5: Solve for x
   x = 7,698,913.78/3,909.39
6. Step 6: Final answer
   x = 1,969.34