Finding the Fourth Proportional to 15,865.23, 21,835.76 and 13,601.69

Step by Step Solution

1. Step 1: Write the proportion equation
   15,865.23 : 21,835.76 = 13,601.69 : x
2. Step 2: Convert to fraction form
   15,865.23/21,835.76 = 13,601.69/x
3. Step 3: Cross multiply
   15,865.23x = 21,835.76 × 13,601.69
4. Step 4: Simplify right side
   15,865.23x = 297,003,061.25
5. Step 5: Solve for x
   x = 297,003,061.25/15,865.23
6. Step 6: Final answer
   x = 18,720.38