Finding the Fourth Proportional to 2,109.60, 2,910.60 and 1,225.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.60 : 2,910.60 = 1,225.56 : x
2. Step 2: Convert to fraction form
   2,109.60/2,910.60 = 1,225.56/x
3. Step 3: Cross multiply
   2,109.60x = 2,910.60 × 1,225.56
4. Step 4: Simplify right side
   2,109.60x = 3,567,114.94
5. Step 5: Solve for x
   x = 3,567,114.94/2,109.60
6. Step 6: Final answer
   x = 1,690.90