Finding the Fourth Proportional to 2,105.41, 2,905.35 and 1,221.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.41 : 2,905.35 = 1,221.50 : x
2. Step 2: Convert to fraction form
   2,105.41/2,905.35 = 1,221.50/x
3. Step 3: Cross multiply
   2,105.41x = 2,905.35 × 1,221.50
4. Step 4: Simplify right side
   2,105.41x = 3,548,885.03
5. Step 5: Solve for x
   x = 3,548,885.03/2,105.41
6. Step 6: Final answer
   x = 1,685.60