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Finding the Fourth Proportional to 386.34, 581.79 and 278.88

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Solution

The fourth proportional to 386.34, 581.79 and 278.88 is: 419.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.34 : 581.79 = 278.88 : x
  2. Step 2: Convert to fraction form
    386.34/581.79 = 278.88/x
  3. Step 3: Cross multiply
    386.34x = 581.79 × 278.88
  4. Step 4: Simplify right side
    386.34x = 162,249.60
  5. Step 5: Solve for x
    x = 162,249.60/386.34
  6. Step 6: Final answer
    x = 419.97

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.