Finding the Fourth Proportional to 2,116.22, 2,920.29 and 1,172.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,116.22 : 2,920.29 = 1,172.05 : x
2. Step 2: Convert to fraction form
   2,116.22/2,920.29 = 1,172.05/x
3. Step 3: Cross multiply
   2,116.22x = 2,920.29 × 1,172.05
4. Step 4: Simplify right side
   2,116.22x = 3,422,711.29
5. Step 5: Solve for x
   x = 3,422,711.29/2,116.22
6. Step 6: Final answer
   x = 1,617.37