Finding the Fourth Proportional to 2,209.78, 3,316.59 and 1,170.53

Step by Step Solution

1. Step 1: Write the proportion equation
   2,209.78 : 3,316.59 = 1,170.53 : x
2. Step 2: Convert to fraction form
   2,209.78/3,316.59 = 1,170.53/x
3. Step 3: Cross multiply
   2,209.78x = 3,316.59 × 1,170.53
4. Step 4: Simplify right side
   2,209.78x = 3,882,145.66
5. Step 5: Solve for x
   x = 3,882,145.66/2,209.78
6. Step 6: Final answer
   x = 1,756.81