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Finding the Fourth Proportional to 384.45, 530.52 and 209.79

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Solution

The fourth proportional to 384.45, 530.52 and 209.79 is: 289.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    384.45 : 530.52 = 209.79 : x
  2. Step 2: Convert to fraction form
    384.45/530.52 = 209.79/x
  3. Step 3: Cross multiply
    384.45x = 530.52 × 209.79
  4. Step 4: Simplify right side
    384.45x = 111,297.79
  5. Step 5: Solve for x
    x = 111,297.79/384.45
  6. Step 6: Final answer
    x = 289.50

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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.