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Finding the Fourth Proportional to 389.34, 530.09 and 388.12

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Solution

The fourth proportional to 389.34, 530.09 and 388.12 is: 528.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.34 : 530.09 = 388.12 : x
  2. Step 2: Convert to fraction form
    389.34/530.09 = 388.12/x
  3. Step 3: Cross multiply
    389.34x = 530.09 × 388.12
  4. Step 4: Simplify right side
    389.34x = 205,736.59
  5. Step 5: Solve for x
    x = 205,736.59/389.34
  6. Step 6: Final answer
    x = 528.43

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.