Finding the Fourth Proportional to 28,007.94, 42,019.20 and 10,479.15

Step by Step Solution

1. Step 1: Write the proportion equation
   28,007.94 : 42,019.20 = 10,479.15 : x
2. Step 2: Convert to fraction form
   28,007.94/42,019.20 = 10,479.15/x
3. Step 3: Cross multiply
   28,007.94x = 42,019.20 × 10,479.15
4. Step 4: Simplify right side
   28,007.94x = 440,325,499.68
5. Step 5: Solve for x
   x = 440,325,499.68/28,007.94
6. Step 6: Final answer
   x = 15,721.45