Finding the Fourth Proportional to 21,870.81, 32,811.42 and 7,079.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,870.81 : 32,811.42 = 7,079.72 : x
2. Step 2: Convert to fraction form
   21,870.81/32,811.42 = 7,079.72/x
3. Step 3: Cross multiply
   21,870.81x = 32,811.42 × 7,079.72
4. Step 4: Simplify right side
   21,870.81x = 232,295,748.43
5. Step 5: Solve for x
   x = 232,295,748.43/21,870.81
6. Step 6: Final answer
   x = 10,621.27