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Finding the Fourth Proportional to 384.40, 530.55 and 218.65

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Solution

The fourth proportional to 384.40, 530.55 and 218.65 is: 301.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    384.40 : 530.55 = 218.65 : x
  2. Step 2: Convert to fraction form
    384.40/530.55 = 218.65/x
  3. Step 3: Cross multiply
    384.40x = 530.55 × 218.65
  4. Step 4: Simplify right side
    384.40x = 116,004.76
  5. Step 5: Solve for x
    x = 116,004.76/384.40
  6. Step 6: Final answer
    x = 301.78

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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.