Finding the Fourth Proportional to 1,144.76, 1,579.77 and 620.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,144.76 : 1,579.77 = 620.79 : x
2. Step 2: Convert to fraction form
   1,144.76/1,579.77 = 620.79/x
3. Step 3: Cross multiply
   1,144.76x = 1,579.77 × 620.79
4. Step 4: Simplify right side
   1,144.76x = 980,701.32
5. Step 5: Solve for x
   x = 980,701.32/1,144.76
6. Step 6: Final answer
   x = 856.69