Finding the Fourth Proportional to 2,478.48, 3,710.16 and 2,128.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,478.48 : 3,710.16 = 2,128.56 : x
2. Step 2: Convert to fraction form
   2,478.48/3,710.16 = 2,128.56/x
3. Step 3: Cross multiply
   2,478.48x = 3,710.16 × 2,128.56
4. Step 4: Simplify right side
   2,478.48x = 7,897,298.17
5. Step 5: Solve for x
   x = 7,897,298.17/2,478.48
6. Step 6: Final answer
   x = 3,186.35