Finding the Fourth Proportional to 2,015.78, 2,781.90 and 1,131.64

Step by Step Solution

1. Step 1: Write the proportion equation
   2,015.78 : 2,781.90 = 1,131.64 : x
2. Step 2: Convert to fraction form
   2,015.78/2,781.90 = 1,131.64/x
3. Step 3: Cross multiply
   2,015.78x = 2,781.90 × 1,131.64
4. Step 4: Simplify right side
   2,015.78x = 3,148,109.32
5. Step 5: Solve for x
   x = 3,148,109.32/2,015.78
6. Step 6: Final answer
   x = 1,561.73