Finding the Fourth Proportional to 13,507.30, 18,638.23 and 7,538.21

Step by Step Solution

1. Step 1: Write the proportion equation
   13,507.30 : 18,638.23 = 7,538.21 : x
2. Step 2: Convert to fraction form
   13,507.30/18,638.23 = 7,538.21/x
3. Step 3: Cross multiply
   13,507.30x = 18,638.23 × 7,538.21
4. Step 4: Simplify right side
   13,507.30x = 140,498,891.77
5. Step 5: Solve for x
   x = 140,498,891.77/13,507.30
6. Step 6: Final answer
   x = 10,401.70