Finding the Fourth Proportional to 3,980.53, 5,961.07 and 2,891.89

Step by Step Solution

1. Step 1: Write the proportion equation
   3,980.53 : 5,961.07 = 2,891.89 : x
2. Step 2: Convert to fraction form
   3,980.53/5,961.07 = 2,891.89/x
3. Step 3: Cross multiply
   3,980.53x = 5,961.07 × 2,891.89
4. Step 4: Simplify right side
   3,980.53x = 17,238,758.72
5. Step 5: Solve for x
   x = 17,238,758.72/3,980.53
6. Step 6: Final answer
   x = 4,330.77