Finding the Fourth Proportional to 16,990.80, 23,447.46 and 9,915.86

Step by Step Solution

1. Step 1: Write the proportion equation
   16,990.80 : 23,447.46 = 9,915.86 : x
2. Step 2: Convert to fraction form
   16,990.80/23,447.46 = 9,915.86/x
3. Step 3: Cross multiply
   16,990.80x = 23,447.46 × 9,915.86
4. Step 4: Simplify right side
   16,990.80x = 232,501,613.48
5. Step 5: Solve for x
   x = 232,501,613.48/16,990.80
6. Step 6: Final answer
   x = 13,683.97