Finding the Fourth Proportional to 1,417.89, 1,956.01 and 1,221.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,417.89 : 1,956.01 = 1,221.06 : x
2. Step 2: Convert to fraction form
   1,417.89/1,956.01 = 1,221.06/x
3. Step 3: Cross multiply
   1,417.89x = 1,956.01 × 1,221.06
4. Step 4: Simplify right side
   1,417.89x = 2,388,405.57
5. Step 5: Solve for x
   x = 2,388,405.57/1,417.89
6. Step 6: Final answer
   x = 1,684.48