Finding the Fourth Proportional to 2,991.69, 4,128.30 and 1,665.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,991.69 : 4,128.30 = 1,665.72 : x
2. Step 2: Convert to fraction form
   2,991.69/4,128.30 = 1,665.72/x
3. Step 3: Cross multiply
   2,991.69x = 4,128.30 × 1,665.72
4. Step 4: Simplify right side
   2,991.69x = 6,876,591.88
5. Step 5: Solve for x
   x = 6,876,591.88/2,991.69
6. Step 6: Final answer
   x = 2,298.56