Finding the Fourth Proportional to 9,411.62, 12,987.45 and 5,219.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,411.62 : 12,987.45 = 5,219.78 : x
2. Step 2: Convert to fraction form
   9,411.62/12,987.45 = 5,219.78/x
3. Step 3: Cross multiply
   9,411.62x = 12,987.45 × 5,219.78
4. Step 4: Simplify right side
   9,411.62x = 67,791,631.76
5. Step 5: Solve for x
   x = 67,791,631.76/9,411.62
6. Step 6: Final answer
   x = 7,202.97