Finding the Fourth Proportional to 2,520.86, 3,780.81 and 672.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,520.86 : 3,780.81 = 672.12 : x
2. Step 2: Convert to fraction form
   2,520.86/3,780.81 = 672.12/x
3. Step 3: Cross multiply
   2,520.86x = 3,780.81 × 672.12
4. Step 4: Simplify right side
   2,520.86x = 2,541,158.02
5. Step 5: Solve for x
   x = 2,541,158.02/2,520.86
6. Step 6: Final answer
   x = 1,008.05