Finding the Fourth Proportional to 4,978.71, 6,871.37 and 2,990.16

Step by Step Solution

1. Step 1: Write the proportion equation
   4,978.71 : 6,871.37 = 2,990.16 : x
2. Step 2: Convert to fraction form
   4,978.71/6,871.37 = 2,990.16/x
3. Step 3: Cross multiply
   4,978.71x = 6,871.37 × 2,990.16
4. Step 4: Simplify right side
   4,978.71x = 20,546,480.77
5. Step 5: Solve for x
   x = 20,546,480.77/4,978.71
6. Step 6: Final answer
   x = 4,126.87