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Finding the Fourth Proportional to 384.45, 530.55 and 209.81

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Solution

The fourth proportional to 384.45, 530.55 and 209.81 is: 289.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    384.45 : 530.55 = 209.81 : x
  2. Step 2: Convert to fraction form
    384.45/530.55 = 209.81/x
  3. Step 3: Cross multiply
    384.45x = 530.55 × 209.81
  4. Step 4: Simplify right side
    384.45x = 111,312.04
  5. Step 5: Solve for x
    x = 111,312.04/384.45
  6. Step 6: Final answer
    x = 289.54

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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.