Finding the Fourth Proportional to 2,117.71, 2,922.16 and 1,221.48

Step by Step Solution

1. Step 1: Write the proportion equation
   2,117.71 : 2,922.16 = 1,221.48 : x
2. Step 2: Convert to fraction form
   2,117.71/2,922.16 = 1,221.48/x
3. Step 3: Cross multiply
   2,117.71x = 2,922.16 × 1,221.48
4. Step 4: Simplify right side
   2,117.71x = 3,569,360.00
5. Step 5: Solve for x
   x = 3,569,360.00/2,117.71
6. Step 6: Final answer
   x = 1,685.48