Finding the Fourth Proportional to 10,290.78, 15,429.69 and 3,715.74

Step by Step Solution

1. Step 1: Write the proportion equation
   10,290.78 : 15,429.69 = 3,715.74 : x
2. Step 2: Convert to fraction form
   10,290.78/15,429.69 = 3,715.74/x
3. Step 3: Cross multiply
   10,290.78x = 15,429.69 × 3,715.74
4. Step 4: Simplify right side
   10,290.78x = 57,332,716.32
5. Step 5: Solve for x
   x = 57,332,716.32/10,290.78
6. Step 6: Final answer
   x = 5,571.27