Finding the Fourth Proportional to 13,643.24, 18,826.34 and 7,674.78

Step by Step Solution

1. Step 1: Write the proportion equation
   13,643.24 : 18,826.34 = 7,674.78 : x
2. Step 2: Convert to fraction form
   13,643.24/18,826.34 = 7,674.78/x
3. Step 3: Cross multiply
   13,643.24x = 18,826.34 × 7,674.78
4. Step 4: Simplify right side
   13,643.24x = 144,488,017.71
5. Step 5: Solve for x
   x = 144,488,017.71/13,643.24
6. Step 6: Final answer
   x = 10,590.45