Finding the Fourth Proportional to 9,145.98, 12,621.18 and 5,419.98

Step by Step Solution

1. Step 1: Write the proportion equation
   9,145.98 : 12,621.18 = 5,419.98 : x
2. Step 2: Convert to fraction form
   9,145.98/12,621.18 = 5,419.98/x
3. Step 3: Cross multiply
   9,145.98x = 12,621.18 × 5,419.98
4. Step 4: Simplify right side
   9,145.98x = 68,406,543.18
5. Step 5: Solve for x
   x = 68,406,543.18/9,145.98
6. Step 6: Final answer
   x = 7,479.41