Finding the Fourth Proportional to 2,102.72, 2,900.20 and 1,543

Step by Step Solution

1. Step 1: Write the proportion equation
   2,102.72 : 2,900.20 = 1,543 : x
2. Step 2: Convert to fraction form
   2,102.72/2,900.20 = 1,543/x
3. Step 3: Cross multiply
   2,102.72x = 2,900.20 × 1,543
4. Step 4: Simplify right side
   2,102.72x = 4,475,008.60
5. Step 5: Solve for x
   x = 4,475,008.60/2,102.72
6. Step 6: Final answer
   x = 2,128.20