Finding the Fourth Proportional to 2,116.01, 2,920.20 and 1,171.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,116.01 : 2,920.20 = 1,171.90 : x
2. Step 2: Convert to fraction form
   2,116.01/2,920.20 = 1,171.90/x
3. Step 3: Cross multiply
   2,116.01x = 2,920.20 × 1,171.90
4. Step 4: Simplify right side
   2,116.01x = 3,422,188.23
5. Step 5: Solve for x
   x = 3,422,188.23/2,116.01
6. Step 6: Final answer
   x = 1,617.29