Finding the Fourth Proportional to 2,111.61, 3,161.73 and 1,981.74

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.61 : 3,161.73 = 1,981.74 : x
2. Step 2: Convert to fraction form
   2,111.61/3,161.73 = 1,981.74/x
3. Step 3: Cross multiply
   2,111.61x = 3,161.73 × 1,981.74
4. Step 4: Simplify right side
   2,111.61x = 6,265,726.81
5. Step 5: Solve for x
   x = 6,265,726.81/2,111.61
6. Step 6: Final answer
   x = 2,967.27