Finding the Fourth Proportional to 13,687.48, 20,554.91 and 13,064.18

Step by Step Solution

1. Step 1: Write the proportion equation
   13,687.48 : 20,554.91 = 13,064.18 : x
2. Step 2: Convert to fraction form
   13,687.48/20,554.91 = 13,064.18/x
3. Step 3: Cross multiply
   13,687.48x = 20,554.91 × 13,064.18
4. Step 4: Simplify right side
   13,687.48x = 268,532,978.80
5. Step 5: Solve for x
   x = 268,532,978.80/13,687.48
6. Step 6: Final answer
   x = 19,618.88