Finding the Fourth Proportional to 1,915.18, 2,644.05 and 1,286.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,915.18 : 2,644.05 = 1,286.62 : x
2. Step 2: Convert to fraction form
   1,915.18/2,644.05 = 1,286.62/x
3. Step 3: Cross multiply
   1,915.18x = 2,644.05 × 1,286.62
4. Step 4: Simplify right side
   1,915.18x = 3,401,887.61
5. Step 5: Solve for x
   x = 3,401,887.61/1,915.18
6. Step 6: Final answer
   x = 1,776.28