Finding the Fourth Proportional to 1,288.35, 1,777.77 and 1,111.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,288.35 : 1,777.77 = 1,111.59 : x
2. Step 2: Convert to fraction form
   1,288.35/1,777.77 = 1,111.59/x
3. Step 3: Cross multiply
   1,288.35x = 1,777.77 × 1,111.59
4. Step 4: Simplify right side
   1,288.35x = 1,976,151.35
5. Step 5: Solve for x
   x = 1,976,151.35/1,288.35
6. Step 6: Final answer
   x = 1,533.86