Finding the Fourth Proportional to 2,121.20, 3,182.00 and 659.96

Step by Step Solution

1. Step 1: Write the proportion equation
   2,121.20 : 3,182.00 = 659.96 : x
2. Step 2: Convert to fraction form
   2,121.20/3,182.00 = 659.96/x
3. Step 3: Cross multiply
   2,121.20x = 3,182.00 × 659.96
4. Step 4: Simplify right side
   2,121.20x = 2,099,973.51
5. Step 5: Solve for x
   x = 2,099,973.51/2,121.20
6. Step 6: Final answer
   x = 990.00