Finding the Fourth Proportional to 7,111.80, 10,666.35 and 2,181.60

Step by Step Solution

1. Step 1: Write the proportion equation
   7,111.80 : 10,666.35 = 2,181.60 : x
2. Step 2: Convert to fraction form
   7,111.80/10,666.35 = 2,181.60/x
3. Step 3: Cross multiply
   7,111.80x = 10,666.35 × 2,181.60
4. Step 4: Simplify right side
   7,111.80x = 23,269,709.16
5. Step 5: Solve for x
   x = 23,269,709.16/7,111.80
6. Step 6: Final answer
   x = 3,271.99