Finding the Fourth Proportional to 31,136.15, 42,968.06 and 16,989.30

Step by Step Solution

1. Step 1: Write the proportion equation
   31,136.15 : 42,968.06 = 16,989.30 : x
2. Step 2: Convert to fraction form
   31,136.15/42,968.06 = 16,989.30/x
3. Step 3: Cross multiply
   31,136.15x = 42,968.06 × 16,989.30
4. Step 4: Simplify right side
   31,136.15x = 729,997,176.81
5. Step 5: Solve for x
   x = 729,997,176.81/31,136.15
6. Step 6: Final answer
   x = 23,445.33