Finding the Fourth Proportional to 2,143.86, 2,958.57 and 1,212.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,143.86 : 2,958.57 = 1,212.18 : x
2. Step 2: Convert to fraction form
   2,143.86/2,958.57 = 1,212.18/x
3. Step 3: Cross multiply
   2,143.86x = 2,958.57 × 1,212.18
4. Step 4: Simplify right side
   2,143.86x = 3,586,319.38
5. Step 5: Solve for x
   x = 3,586,319.38/2,143.86
6. Step 6: Final answer
   x = 1,672.83