Finding the Fourth Proportional to 1,109.78, 1,530.52 and 888.65

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.78 : 1,530.52 = 888.65 : x
2. Step 2: Convert to fraction form
   1,109.78/1,530.52 = 888.65/x
3. Step 3: Cross multiply
   1,109.78x = 1,530.52 × 888.65
4. Step 4: Simplify right side
   1,109.78x = 1,360,084.50
5. Step 5: Solve for x
   x = 1,360,084.50/1,109.78
6. Step 6: Final answer
   x = 1,225.55