Finding the Fourth Proportional to 39,870.56, 55,022.78 and 21,966.93

Step by Step Solution

1. Step 1: Write the proportion equation
   39,870.56 : 55,022.78 = 21,966.93 : x
2. Step 2: Convert to fraction form
   39,870.56/55,022.78 = 21,966.93/x
3. Step 3: Cross multiply
   39,870.56x = 55,022.78 × 21,966.93
4. Step 4: Simplify right side
   39,870.56x = 1,208,681,556.67
5. Step 5: Solve for x
   x = 1,208,681,556.67/39,870.56
6. Step 6: Final answer
   x = 30,315.14