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Finding the Fourth Proportional to 509.28, 702.80 and 285.21

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Solution

The fourth proportional to 509.28, 702.80 and 285.21 is: 393.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.28 : 702.80 = 285.21 : x
  2. Step 2: Convert to fraction form
    509.28/702.80 = 285.21/x
  3. Step 3: Cross multiply
    509.28x = 702.80 × 285.21
  4. Step 4: Simplify right side
    509.28x = 200,444.16
  5. Step 5: Solve for x
    x = 200,444.16/509.28
  6. Step 6: Final answer
    x = 393.58

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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.