Finding the Fourth Proportional to 1,079.50, 1,489.72 and 613.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,079.50 : 1,489.72 = 613.76 : x
2. Step 2: Convert to fraction form
   1,079.50/1,489.72 = 613.76/x
3. Step 3: Cross multiply
   1,079.50x = 1,489.72 × 613.76
4. Step 4: Simplify right side
   1,079.50x = 914,330.55
5. Step 5: Solve for x
   x = 914,330.55/1,079.50
6. Step 6: Final answer
   x = 846.99