Finding the Fourth Proportional to 12,638.64, 17,439.60 and 7,333.20

Step by Step Solution

1. Step 1: Write the proportion equation
   12,638.64 : 17,439.60 = 7,333.20 : x
2. Step 2: Convert to fraction form
   12,638.64/17,439.60 = 7,333.20/x
3. Step 3: Cross multiply
   12,638.64x = 17,439.60 × 7,333.20
4. Step 4: Simplify right side
   12,638.64x = 127,888,074.72
5. Step 5: Solve for x
   x = 127,888,074.72/12,638.64
6. Step 6: Final answer
   x = 10,118.82