Finding the Fourth Proportional to 15,685.98, 21,645.30 and 8,970.52

Step by Step Solution

1. Step 1: Write the proportion equation
   15,685.98 : 21,645.30 = 8,970.52 : x
2. Step 2: Convert to fraction form
   15,685.98/21,645.30 = 8,970.52/x
3. Step 3: Cross multiply
   15,685.98x = 21,645.30 × 8,970.52
4. Step 4: Simplify right side
   15,685.98x = 194,169,596.56
5. Step 5: Solve for x
   x = 194,169,596.56/15,685.98
6. Step 6: Final answer
   x = 12,378.54