Finding the Fourth Proportional to 2,143.59, 2,958.06 and 1,212.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,143.59 : 2,958.06 = 1,212.09 : x
2. Step 2: Convert to fraction form
   2,143.59/2,958.06 = 1,212.09/x
3. Step 3: Cross multiply
   2,143.59x = 2,958.06 × 1,212.09
4. Step 4: Simplify right side
   2,143.59x = 3,585,434.95
5. Step 5: Solve for x
   x = 3,585,434.95/2,143.59
6. Step 6: Final answer
   x = 1,672.63