Finding the Fourth Proportional to 25,719.71, 35,499.78 and 15,655.21

Step by Step Solution

1. Step 1: Write the proportion equation
   25,719.71 : 35,499.78 = 15,655.21 : x
2. Step 2: Convert to fraction form
   25,719.71/35,499.78 = 15,655.21/x
3. Step 3: Cross multiply
   25,719.71x = 35,499.78 × 15,655.21
4. Step 4: Simplify right side
   25,719.71x = 555,756,422.10
5. Step 5: Solve for x
   x = 555,756,422.10/25,719.71
6. Step 6: Final answer
   x = 21,608.20