Finding the Fourth Proportional to 2,072.31, 2,859.57 and 1,187.88

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.31 : 2,859.57 = 1,187.88 : x
2. Step 2: Convert to fraction form
   2,072.31/2,859.57 = 1,187.88/x
3. Step 3: Cross multiply
   2,072.31x = 2,859.57 × 1,187.88
4. Step 4: Simplify right side
   2,072.31x = 3,396,826.01
5. Step 5: Solve for x
   x = 3,396,826.01/2,072.31
6. Step 6: Final answer
   x = 1,639.15