Finding the Fourth Proportional to 15,643.62, 21,587.98 and 8,570.09

Step by Step Solution

1. Step 1: Write the proportion equation
   15,643.62 : 21,587.98 = 8,570.09 : x
2. Step 2: Convert to fraction form
   15,643.62/21,587.98 = 8,570.09/x
3. Step 3: Cross multiply
   15,643.62x = 21,587.98 × 8,570.09
4. Step 4: Simplify right side
   15,643.62x = 185,010,931.52
5. Step 5: Solve for x
   x = 185,010,931.52/15,643.62
6. Step 6: Final answer
   x = 11,826.61