Finding the Fourth Proportional to 2,666.50, 3,673.94 and 1,991.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,666.50 : 3,673.94 = 1,991.50 : x
2. Step 2: Convert to fraction form
   2,666.50/3,673.94 = 1,991.50/x
3. Step 3: Cross multiply
   2,666.50x = 3,673.94 × 1,991.50
4. Step 4: Simplify right side
   2,666.50x = 7,316,651.51
5. Step 5: Solve for x
   x = 7,316,651.51/2,666.50
6. Step 6: Final answer
   x = 2,743.92