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Finding the Fourth Proportional to 603.03, 903.30 and 420.78

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Solution

The fourth proportional to 603.03, 903.30 and 420.78 is: 630.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    603.03 : 903.30 = 420.78 : x
  2. Step 2: Convert to fraction form
    603.03/903.30 = 420.78/x
  3. Step 3: Cross multiply
    603.03x = 903.30 × 420.78
  4. Step 4: Simplify right side
    603.03x = 380,090.57
  5. Step 5: Solve for x
    x = 380,090.57/603.03
  6. Step 6: Final answer
    x = 630.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.