Finding the Fourth Proportional to 30,585.48, 42,221.21 and 28,670.42

Step by Step Solution

1. Step 1: Write the proportion equation
   30,585.48 : 42,221.21 = 28,670.42 : x
2. Step 2: Convert to fraction form
   30,585.48/42,221.21 = 28,670.42/x
3. Step 3: Cross multiply
   30,585.48x = 42,221.21 × 28,670.42
4. Step 4: Simplify right side
   30,585.48x = 1,210,499,469.15
5. Step 5: Solve for x
   x = 1,210,499,469.15/30,585.48
6. Step 6: Final answer
   x = 39,577.59