Finding the Fourth Proportional to 1,111.76, 1,533.76 and 780.41

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.76 : 1,533.76 = 780.41 : x
2. Step 2: Convert to fraction form
   1,111.76/1,533.76 = 780.41/x
3. Step 3: Cross multiply
   1,111.76x = 1,533.76 × 780.41
4. Step 4: Simplify right side
   1,111.76x = 1,196,961.64
5. Step 5: Solve for x
   x = 1,196,961.64/1,111.76
6. Step 6: Final answer
   x = 1,076.64