Finding the Fourth Proportional to 2,111.53, 2,897.88 and 1,987.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.53 : 2,897.88 = 1,987.87 : x
2. Step 2: Convert to fraction form
   2,111.53/2,897.88 = 1,987.87/x
3. Step 3: Cross multiply
   2,111.53x = 2,897.88 × 1,987.87
4. Step 4: Simplify right side
   2,111.53x = 5,760,608.72
5. Step 5: Solve for x
   x = 5,760,608.72/2,111.53
6. Step 6: Final answer
   x = 2,728.17