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Finding the Fourth Proportional to 387.17, 579.90 and 278.63

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Solution

The fourth proportional to 387.17, 579.90 and 278.63 is: 417.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.17 : 579.90 = 278.63 : x
  2. Step 2: Convert to fraction form
    387.17/579.90 = 278.63/x
  3. Step 3: Cross multiply
    387.17x = 579.90 × 278.63
  4. Step 4: Simplify right side
    387.17x = 161,577.54
  5. Step 5: Solve for x
    x = 161,577.54/387.17
  6. Step 6: Final answer
    x = 417.33

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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.