Finding the Fourth Proportional to 1,145.50, 1,580.79 and 679.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.50 : 1,580.79 = 679.84 : x
2. Step 2: Convert to fraction form
   1,145.50/1,580.79 = 679.84/x
3. Step 3: Cross multiply
   1,145.50x = 1,580.79 × 679.84
4. Step 4: Simplify right side
   1,145.50x = 1,074,684.27
5. Step 5: Solve for x
   x = 1,074,684.27/1,145.50
6. Step 6: Final answer
   x = 938.18