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Finding the Fourth Proportional to 387.28, 581.04 and 306.40

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Solution

The fourth proportional to 387.28, 581.04 and 306.40 is: 459.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.28 : 581.04 = 306.40 : x
  2. Step 2: Convert to fraction form
    387.28/581.04 = 306.40/x
  3. Step 3: Cross multiply
    387.28x = 581.04 × 306.40
  4. Step 4: Simplify right side
    387.28x = 178,030.66
  5. Step 5: Solve for x
    x = 178,030.66/387.28
  6. Step 6: Final answer
    x = 459.69

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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.