Finding the Fourth Proportional to 1,087.42, 1,627.37 and 670.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,087.42 : 1,627.37 = 670.78 : x
2. Step 2: Convert to fraction form
   1,087.42/1,627.37 = 670.78/x
3. Step 3: Cross multiply
   1,087.42x = 1,627.37 × 670.78
4. Step 4: Simplify right side
   1,087.42x = 1,091,607.25
5. Step 5: Solve for x
   x = 1,091,607.25/1,087.42
6. Step 6: Final answer
   x = 1,003.85