Finding the Fourth Proportional to 1,002.42, 1,503.45 and 425.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,002.42 : 1,503.45 = 425.34 : x
2. Step 2: Convert to fraction form
   1,002.42/1,503.45 = 425.34/x
3. Step 3: Cross multiply
   1,002.42x = 1,503.45 × 425.34
4. Step 4: Simplify right side
   1,002.42x = 639,477.42
5. Step 5: Solve for x
   x = 639,477.42/1,002.42
6. Step 6: Final answer
   x = 637.93