Finding the Fourth Proportional to 2,105.32, 2,905.06 and 1,221.08

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.32 : 2,905.06 = 1,221.08 : x
2. Step 2: Convert to fraction form
   2,105.32/2,905.06 = 1,221.08/x
3. Step 3: Cross multiply
   2,105.32x = 2,905.06 × 1,221.08
4. Step 4: Simplify right side
   2,105.32x = 3,547,310.66
5. Step 5: Solve for x
   x = 3,547,310.66/2,105.32
6. Step 6: Final answer
   x = 1,684.93