Finding the Fourth Proportional to 2,153.46, 2,971.69 and 1,221.96

Step by Step Solution

1. Step 1: Write the proportion equation
   2,153.46 : 2,971.69 = 1,221.96 : x
2. Step 2: Convert to fraction form
   2,153.46/2,971.69 = 1,221.96/x
3. Step 3: Cross multiply
   2,153.46x = 2,971.69 × 1,221.96
4. Step 4: Simplify right side
   2,153.46x = 3,631,286.31
5. Step 5: Solve for x
   x = 3,631,286.31/2,153.46
6. Step 6: Final answer
   x = 1,686.26