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Finding the Fourth Proportional to 420.18, 579.74 and 254.47

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Solution

The fourth proportional to 420.18, 579.74 and 254.47 is: 351.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.18 : 579.74 = 254.47 : x
  2. Step 2: Convert to fraction form
    420.18/579.74 = 254.47/x
  3. Step 3: Cross multiply
    420.18x = 579.74 × 254.47
  4. Step 4: Simplify right side
    420.18x = 147,526.44
  5. Step 5: Solve for x
    x = 147,526.44/420.18
  6. Step 6: Final answer
    x = 351.10

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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.