Finding the Fourth Proportional to 2,072.31, 2,859.87 and 1,188.19

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.31 : 2,859.87 = 1,188.19 : x
2. Step 2: Convert to fraction form
   2,072.31/2,859.87 = 1,188.19/x
3. Step 3: Cross multiply
   2,072.31x = 2,859.87 × 1,188.19
4. Step 4: Simplify right side
   2,072.31x = 3,398,068.94
5. Step 5: Solve for x
   x = 3,398,068.94/2,072.31
6. Step 6: Final answer
   x = 1,639.75