Finding the Fourth Proportional to 2,080.76, 3,120.86 and 619.64

Step by Step Solution

1. Step 1: Write the proportion equation
   2,080.76 : 3,120.86 = 619.64 : x
2. Step 2: Convert to fraction form
   2,080.76/3,120.86 = 619.64/x
3. Step 3: Cross multiply
   2,080.76x = 3,120.86 × 619.64
4. Step 4: Simplify right side
   2,080.76x = 1,933,809.69
5. Step 5: Solve for x
   x = 1,933,809.69/2,080.76
6. Step 6: Final answer
   x = 929.38