Finding the Third Proportional to 2,421.56 and 3,920.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,421.56 : 3,920.91 = 3,920.91 : x
2. Step 2: Convert to fraction form
   2,421.56/3,920.91 = 3,920.91/x
3. Step 3: Cross multiply
   2,421.56x = 3,920.91 × 3,920.91
4. Step 4: Simplify right side
   2,421.56x = 15,373,505.82
5. Step 5: Solve for x
   x = 15,373,505.82/2,421.56
6. Step 6: Final answer
   x = 6,348.59