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Finding the Fourth Proportional to 420.05, 579.42 and 254.21

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Solution

The fourth proportional to 420.05, 579.42 and 254.21 is: 350.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.05 : 579.42 = 254.21 : x
  2. Step 2: Convert to fraction form
    420.05/579.42 = 254.21/x
  3. Step 3: Cross multiply
    420.05x = 579.42 × 254.21
  4. Step 4: Simplify right side
    420.05x = 147,291.46
  5. Step 5: Solve for x
    x = 147,291.46/420.05
  6. Step 6: Final answer
    x = 350.65

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.