Finding the Fourth Proportional to 2,086.56, 2,880.36 and 1,386.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.56 : 2,880.36 = 1,386.72 : x
2. Step 2: Convert to fraction form
   2,086.56/2,880.36 = 1,386.72/x
3. Step 3: Cross multiply
   2,086.56x = 2,880.36 × 1,386.72
4. Step 4: Simplify right side
   2,086.56x = 3,994,252.82
5. Step 5: Solve for x
   x = 3,994,252.82/2,086.56
6. Step 6: Final answer
   x = 1,914.28