Finding the Fourth Proportional to 42,728.10, 64,066.55 and 21,992.10

Step by Step Solution

1. Step 1: Write the proportion equation
   42,728.10 : 64,066.55 = 21,992.10 : x
2. Step 2: Convert to fraction form
   42,728.10/64,066.55 = 21,992.10/x
3. Step 3: Cross multiply
   42,728.10x = 64,066.55 × 21,992.10
4. Step 4: Simplify right side
   42,728.10x = 1,408,957,974.26
5. Step 5: Solve for x
   x = 1,408,957,974.26/42,728.10
6. Step 6: Final answer
   x = 32,974.97