Finding the Fourth Proportional to 2,390.42, 3,298.80 and 1,328.21

Step by Step Solution

1. Step 1: Write the proportion equation
   2,390.42 : 3,298.80 = 1,328.21 : x
2. Step 2: Convert to fraction form
   2,390.42/3,298.80 = 1,328.21/x
3. Step 3: Cross multiply
   2,390.42x = 3,298.80 × 1,328.21
4. Step 4: Simplify right side
   2,390.42x = 4,381,499.15
5. Step 5: Solve for x
   x = 4,381,499.15/2,390.42
6. Step 6: Final answer
   x = 1,832.94