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Finding the Fourth Proportional to 419.28, 581.35 and 397.40

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Solution

The fourth proportional to 419.28, 581.35 and 397.40 is: 551.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.28 : 581.35 = 397.40 : x
  2. Step 2: Convert to fraction form
    419.28/581.35 = 397.40/x
  3. Step 3: Cross multiply
    419.28x = 581.35 × 397.40
  4. Step 4: Simplify right side
    419.28x = 231,028.49
  5. Step 5: Solve for x
    x = 231,028.49/419.28
  6. Step 6: Final answer
    x = 551.01

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.