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Finding the Fourth Proportional to 409.70, 611.30 and 355.70

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Solution

The fourth proportional to 409.70, 611.30 and 355.70 is: 530.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.70 : 611.30 = 355.70 : x
  2. Step 2: Convert to fraction form
    409.70/611.30 = 355.70/x
  3. Step 3: Cross multiply
    409.70x = 611.30 × 355.70
  4. Step 4: Simplify right side
    409.70x = 217,439.41
  5. Step 5: Solve for x
    x = 217,439.41/409.70
  6. Step 6: Final answer
    x = 530.73

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.