Finding the Fourth Proportional to 2,991.89, 4,128.71 and 1,665.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,991.89 : 4,128.71 = 1,665.56 : x
2. Step 2: Convert to fraction form
   2,991.89/4,128.71 = 1,665.56/x
3. Step 3: Cross multiply
   2,991.89x = 4,128.71 × 1,665.56
4. Step 4: Simplify right side
   2,991.89x = 6,876,628.71
5. Step 5: Solve for x
   x = 6,876,628.71/2,991.89
6. Step 6: Final answer
   x = 2,298.43