Finding the Fourth Proportional to 5,780.74, 7,974.35 and 3,889.10

Step by Step Solution

1. Step 1: Write the proportion equation
   5,780.74 : 7,974.35 = 3,889.10 : x
2. Step 2: Convert to fraction form
   5,780.74/7,974.35 = 3,889.10/x
3. Step 3: Cross multiply
   5,780.74x = 7,974.35 × 3,889.10
4. Step 4: Simplify right side
   5,780.74x = 31,013,048.45
5. Step 5: Solve for x
   x = 31,013,048.45/5,780.74
6. Step 6: Final answer
   x = 5,364.89