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Finding the Fourth Proportional to 385.09, 530.69 and 280.07

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Solution

The fourth proportional to 385.09, 530.69 and 280.07 is: 385.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.09 : 530.69 = 280.07 : x
  2. Step 2: Convert to fraction form
    385.09/530.69 = 280.07/x
  3. Step 3: Cross multiply
    385.09x = 530.69 × 280.07
  4. Step 4: Simplify right side
    385.09x = 148,630.27
  5. Step 5: Solve for x
    x = 148,630.27/385.09
  6. Step 6: Final answer
    x = 385.96

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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.