Finding the Fourth Proportional to 3,994.64, 5,992.72 and 1,221

Step by Step Solution

1. Step 1: Write the proportion equation
   3,994.64 : 5,992.72 = 1,221 : x
2. Step 2: Convert to fraction form
   3,994.64/5,992.72 = 1,221/x
3. Step 3: Cross multiply
   3,994.64x = 5,992.72 × 1,221
4. Step 4: Simplify right side
   3,994.64x = 7,317,111.12
5. Step 5: Solve for x
   x = 7,317,111.12/3,994.64
6. Step 6: Final answer
   x = 1,831.73