Finding the Fourth Proportional to 11,187.88, 15,412.56 and 7,824.40

Step by Step Solution

1. Step 1: Write the proportion equation
   11,187.88 : 15,412.56 = 7,824.40 : x
2. Step 2: Convert to fraction form
   11,187.88/15,412.56 = 7,824.40/x
3. Step 3: Cross multiply
   11,187.88x = 15,412.56 × 7,824.40
4. Step 4: Simplify right side
   11,187.88x = 120,594,034.46
5. Step 5: Solve for x
   x = 120,594,034.46/11,187.88
6. Step 6: Final answer
   x = 10,778.99