Finding the Fourth Proportional to 2,172.41, 2,997.35 and 1,287.81

Step by Step Solution

1. Step 1: Write the proportion equation
   2,172.41 : 2,997.35 = 1,287.81 : x
2. Step 2: Convert to fraction form
   2,172.41/2,997.35 = 1,287.81/x
3. Step 3: Cross multiply
   2,172.41x = 2,997.35 × 1,287.81
4. Step 4: Simplify right side
   2,172.41x = 3,860,010.86
5. Step 5: Solve for x
   x = 3,860,010.86/2,172.41
6. Step 6: Final answer
   x = 1,776.84