Finding the Fourth Proportional to 1,150.68, 1,587.78 and 678.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,150.68 : 1,587.78 = 678.60 : x
2. Step 2: Convert to fraction form
   1,150.68/1,587.78 = 678.60/x
3. Step 3: Cross multiply
   1,150.68x = 1,587.78 × 678.60
4. Step 4: Simplify right side
   1,150.68x = 1,077,467.51
5. Step 5: Solve for x
   x = 1,077,467.51/1,150.68
6. Step 6: Final answer
   x = 936.37