Finding the Fourth Proportional to 13,490.32, 18,615.28 and 7,521.43

Step by Step Solution

1. Step 1: Write the proportion equation
   13,490.32 : 18,615.28 = 7,521.43 : x
2. Step 2: Convert to fraction form
   13,490.32/18,615.28 = 7,521.43/x
3. Step 3: Cross multiply
   13,490.32x = 18,615.28 × 7,521.43
4. Step 4: Simplify right side
   13,490.32x = 140,013,394.77
5. Step 5: Solve for x
   x = 140,013,394.77/13,490.32
6. Step 6: Final answer
   x = 10,378.81