Finding the Fourth Proportional to 2,118.32, 2,922.89 and 1,221.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,118.32 : 2,922.89 = 1,221.84 : x
2. Step 2: Convert to fraction form
   2,118.32/2,922.89 = 1,221.84/x
3. Step 3: Cross multiply
   2,118.32x = 2,922.89 × 1,221.84
4. Step 4: Simplify right side
   2,118.32x = 3,571,297.81
5. Step 5: Solve for x
   x = 3,571,297.81/2,118.32
6. Step 6: Final answer
   x = 1,685.91