Finding the Fourth Proportional to 30,415.42, 42,002.15 and 28,758.77

Step by Step Solution

1. Step 1: Write the proportion equation
   30,415.42 : 42,002.15 = 28,758.77 : x
2. Step 2: Convert to fraction form
   30,415.42/42,002.15 = 28,758.77/x
3. Step 3: Cross multiply
   30,415.42x = 42,002.15 × 28,758.77
4. Step 4: Simplify right side
   30,415.42x = 1,207,929,961.34
5. Step 5: Solve for x
   x = 1,207,929,961.34/30,415.42
6. Step 6: Final answer
   x = 39,714.39