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Finding the Fourth Proportional to 312.40, 434.55 and 306.46

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Solution

The fourth proportional to 312.40, 434.55 and 306.46 is: 426.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.40 : 434.55 = 306.46 : x
  2. Step 2: Convert to fraction form
    312.40/434.55 = 306.46/x
  3. Step 3: Cross multiply
    312.40x = 434.55 × 306.46
  4. Step 4: Simplify right side
    312.40x = 133,170.02
  5. Step 5: Solve for x
    x = 133,170.02/312.40
  6. Step 6: Final answer
    x = 426.29

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.