Finding the Fourth Proportional to 21,031.32, 31,377.34 and 20,265.60

Step by Step Solution

1. Step 1: Write the proportion equation
   21,031.32 : 31,377.34 = 20,265.60 : x
2. Step 2: Convert to fraction form
   21,031.32/31,377.34 = 20,265.60/x
3. Step 3: Cross multiply
   21,031.32x = 31,377.34 × 20,265.60
4. Step 4: Simplify right side
   21,031.32x = 635,880,621.50
5. Step 5: Solve for x
   x = 635,880,621.50/21,031.32
6. Step 6: Final answer
   x = 30,234.94