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Finding the Fourth Proportional to 419.82, 630.94 and 389.64

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Solution

The fourth proportional to 419.82, 630.94 and 389.64 is: 585.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.82 : 630.94 = 389.64 : x
  2. Step 2: Convert to fraction form
    419.82/630.94 = 389.64/x
  3. Step 3: Cross multiply
    419.82x = 630.94 × 389.64
  4. Step 4: Simplify right side
    419.82x = 245,839.46
  5. Step 5: Solve for x
    x = 245,839.46/419.82
  6. Step 6: Final answer
    x = 585.58

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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.