Finding the Fourth Proportional to 39,870, 55,023.12 and 21,965.04

Step by Step Solution

1. Step 1: Write the proportion equation
   39,870 : 55,023.12 = 21,965.04 : x
2. Step 2: Convert to fraction form
   39,870/55,023.12 = 21,965.04/x
3. Step 3: Cross multiply
   39,870x = 55,023.12 × 21,965.04
4. Step 4: Simplify right side
   39,870x = 1,208,585,031.72
5. Step 5: Solve for x
   x = 1,208,585,031.72/39,870
6. Step 6: Final answer
   x = 30,313.14