Finding the Fourth Proportional to 2,167.03, 2,990.49 and 1,172.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,167.03 : 2,990.49 = 1,172.31 : x
2. Step 2: Convert to fraction form
   2,167.03/2,990.49 = 1,172.31/x
3. Step 3: Cross multiply
   2,167.03x = 2,990.49 × 1,172.31
4. Step 4: Simplify right side
   2,167.03x = 3,505,772.32
5. Step 5: Solve for x
   x = 3,505,772.32/2,167.03
6. Step 6: Final answer
   x = 1,617.78