Finding the Fourth Proportional to 11,980.78, 17,970.52 and 3,660.06

Step by Step Solution

1. Step 1: Write the proportion equation
   11,980.78 : 17,970.52 = 3,660.06 : x
2. Step 2: Convert to fraction form
   11,980.78/17,970.52 = 3,660.06/x
3. Step 3: Cross multiply
   11,980.78x = 17,970.52 × 3,660.06
4. Step 4: Simplify right side
   11,980.78x = 65,773,181.43
5. Step 5: Solve for x
   x = 65,773,181.43/11,980.78
6. Step 6: Final answer
   x = 5,489.89