Finding the Fourth Proportional to 13,643.21, 18,826.61 and 7,673.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13,643.21 : 18,826.61 = 7,673.72 : x
2. Step 2: Convert to fraction form
   13,643.21/18,826.61 = 7,673.72/x
3. Step 3: Cross multiply
   13,643.21x = 18,826.61 × 7,673.72
4. Step 4: Simplify right side
   13,643.21x = 144,470,166.06
5. Step 5: Solve for x
   x = 144,470,166.06/13,643.21
6. Step 6: Final answer
   x = 10,589.17