Finding the Fourth Proportional to 51,390.72, 70,919.52 and 28,419.84

Step by Step Solution

1. Step 1: Write the proportion equation
   51,390.72 : 70,919.52 = 28,419.84 : x
2. Step 2: Convert to fraction form
   51,390.72/70,919.52 = 28,419.84/x
3. Step 3: Cross multiply
   51,390.72x = 70,919.52 × 28,419.84
4. Step 4: Simplify right side
   51,390.72x = 2,015,521,411.28
5. Step 5: Solve for x
   x = 2,015,521,411.28/51,390.72
6. Step 6: Final answer
   x = 39,219.56