Finding the Fourth Proportional to 1,208.42, 1,667.91 and 788.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,208.42 : 1,667.91 = 788.06 : x
2. Step 2: Convert to fraction form
   1,208.42/1,667.91 = 788.06/x
3. Step 3: Cross multiply
   1,208.42x = 1,667.91 × 788.06
4. Step 4: Simplify right side
   1,208.42x = 1,314,415.85
5. Step 5: Solve for x
   x = 1,314,415.85/1,208.42
6. Step 6: Final answer
   x = 1,087.72