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Finding the Fourth Proportional to 420.15, 579.84 and 254.37

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Solution

The fourth proportional to 420.15, 579.84 and 254.37 is: 351.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.15 : 579.84 = 254.37 : x
  2. Step 2: Convert to fraction form
    420.15/579.84 = 254.37/x
  3. Step 3: Cross multiply
    420.15x = 579.84 × 254.37
  4. Step 4: Simplify right side
    420.15x = 147,493.90
  5. Step 5: Solve for x
    x = 147,493.90/420.15
  6. Step 6: Final answer
    x = 351.05

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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.