Finding the Fourth Proportional to 13,196.81, 18,211.68 and 7,228.53

Step by Step Solution

1. Step 1: Write the proportion equation
   13,196.81 : 18,211.68 = 7,228.53 : x
2. Step 2: Convert to fraction form
   13,196.81/18,211.68 = 7,228.53/x
3. Step 3: Cross multiply
   13,196.81x = 18,211.68 × 7,228.53
4. Step 4: Simplify right side
   13,196.81x = 131,643,675.23
5. Step 5: Solve for x
   x = 131,643,675.23/13,196.81
6. Step 6: Final answer
   x = 9,975.41