Finding the Fourth Proportional to 13,214.44, 19,818.78 and 3,978.28

Step by Step Solution

1. Step 1: Write the proportion equation
   13,214.44 : 19,818.78 = 3,978.28 : x
2. Step 2: Convert to fraction form
   13,214.44/19,818.78 = 3,978.28/x
3. Step 3: Cross multiply
   13,214.44x = 19,818.78 × 3,978.28
4. Step 4: Simplify right side
   13,214.44x = 78,844,656.10
5. Step 5: Solve for x
   x = 78,844,656.10/13,214.44
6. Step 6: Final answer
   x = 5,966.55