Finding the Fourth Proportional to 13,309.31, 19,968.66 and 5,913.09

Step by Step Solution

1. Step 1: Write the proportion equation
   13,309.31 : 19,968.66 = 5,913.09 : x
2. Step 2: Convert to fraction form
   13,309.31/19,968.66 = 5,913.09/x
3. Step 3: Cross multiply
   13,309.31x = 19,968.66 × 5,913.09
4. Step 4: Simplify right side
   13,309.31x = 118,076,483.76
5. Step 5: Solve for x
   x = 118,076,483.76/13,309.31
6. Step 6: Final answer
   x = 8,871.72