Finding the Fourth Proportional to 2,142.30, 3,005.70 and 2,142.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,142.30 : 3,005.70 = 2,142.30 : x
2. Step 2: Convert to fraction form
   2,142.30/3,005.70 = 2,142.30/x
3. Step 3: Cross multiply
   2,142.30x = 3,005.70 × 2,142.30
4. Step 4: Simplify right side
   2,142.30x = 6,439,111.11
5. Step 5: Solve for x
   x = 6,439,111.11/2,142.30
6. Step 6: Final answer
   x = 3,005.70