Finding the Fourth Proportional to 2,156.72, 2,976.26 and 1,225.22

Step by Step Solution

1. Step 1: Write the proportion equation
   2,156.72 : 2,976.26 = 1,225.22 : x
2. Step 2: Convert to fraction form
   2,156.72/2,976.26 = 1,225.22/x
3. Step 3: Cross multiply
   2,156.72x = 2,976.26 × 1,225.22
4. Step 4: Simplify right side
   2,156.72x = 3,646,573.28
5. Step 5: Solve for x
   x = 3,646,573.28/2,156.72
6. Step 6: Final answer
   x = 1,690.80