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Finding the Fourth Proportional to 420.10, 579.64 and 254.38

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Solution

The fourth proportional to 420.10, 579.64 and 254.38 is: 350.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.10 : 579.64 = 254.38 : x
  2. Step 2: Convert to fraction form
    420.10/579.64 = 254.38/x
  3. Step 3: Cross multiply
    420.10x = 579.64 × 254.38
  4. Step 4: Simplify right side
    420.10x = 147,448.82
  5. Step 5: Solve for x
    x = 147,448.82/420.10
  6. Step 6: Final answer
    x = 350.99

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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.