Finding the Fourth Proportional to 2,619.34, 3,926.58 and 886.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,619.34 : 3,926.58 = 886.78 : x
2. Step 2: Convert to fraction form
   2,619.34/3,926.58 = 886.78/x
3. Step 3: Cross multiply
   2,619.34x = 3,926.58 × 886.78
4. Step 4: Simplify right side
   2,619.34x = 3,482,012.61
5. Step 5: Solve for x
   x = 3,482,012.61/2,619.34
6. Step 6: Final answer
   x = 1,329.35