Finding the Fourth Proportional to 1,987.52, 2,978.24 and 1,335.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,987.52 : 2,978.24 = 1,335.84 : x
2. Step 2: Convert to fraction form
   1,987.52/2,978.24 = 1,335.84/x
3. Step 3: Cross multiply
   1,987.52x = 2,978.24 × 1,335.84
4. Step 4: Simplify right side
   1,987.52x = 3,978,452.12
5. Step 5: Solve for x
   x = 3,978,452.12/1,987.52
6. Step 6: Final answer
   x = 2,001.72