Finding the Fourth Proportional to 830.19, 1,145.61 and 498.42

Step by Step Solution

1. Step 1: Write the proportion equation
   830.19 : 1,145.61 = 498.42 : x
2. Step 2: Convert to fraction form
   830.19/1,145.61 = 498.42/x
3. Step 3: Cross multiply
   830.19x = 1,145.61 × 498.42
4. Step 4: Simplify right side
   830.19x = 570,994.94
5. Step 5: Solve for x
   x = 570,994.94/830.19
6. Step 6: Final answer
   x = 687.79