Finding the Fourth Proportional to 2,109.77, 2,910.99 and 1,225.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.77 : 2,910.99 = 1,225.42 : x
2. Step 2: Convert to fraction form
   2,109.77/2,910.99 = 1,225.42/x
3. Step 3: Cross multiply
   2,109.77x = 2,910.99 × 1,225.42
4. Step 4: Simplify right side
   2,109.77x = 3,567,185.37
5. Step 5: Solve for x
   x = 3,567,185.37/2,109.77
6. Step 6: Final answer
   x = 1,690.79