Finding the Fourth Proportional to 12,784.90, 19,152.78 and 7,840.12

Step by Step Solution

1. Step 1: Write the proportion equation
   12,784.90 : 19,152.78 = 7,840.12 : x
2. Step 2: Convert to fraction form
   12,784.90/19,152.78 = 7,840.12/x
3. Step 3: Cross multiply
   12,784.90x = 19,152.78 × 7,840.12
4. Step 4: Simplify right side
   12,784.90x = 150,160,093.53
5. Step 5: Solve for x
   x = 150,160,093.53/12,784.90
6. Step 6: Final answer
   x = 11,745.11