Finding the Fourth Proportional to 1,003.42, 1,505.38 and 345.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.42 : 1,505.38 = 345.30 : x
2. Step 2: Convert to fraction form
   1,003.42/1,505.38 = 345.30/x
3. Step 3: Cross multiply
   1,003.42x = 1,505.38 × 345.30
4. Step 4: Simplify right side
   1,003.42x = 519,807.71
5. Step 5: Solve for x
   x = 519,807.71/1,003.42
6. Step 6: Final answer
   x = 518.04