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Finding the Fourth Proportional to 420.60, 628.90 and 383.84

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Solution

The fourth proportional to 420.60, 628.90 and 383.84 is: 573.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.60 : 628.90 = 383.84 : x
  2. Step 2: Convert to fraction form
    420.60/628.90 = 383.84/x
  3. Step 3: Cross multiply
    420.60x = 628.90 × 383.84
  4. Step 4: Simplify right side
    420.60x = 241,399.94
  5. Step 5: Solve for x
    x = 241,399.94/420.60
  6. Step 6: Final answer
    x = 573.94

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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.