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Finding the Fourth Proportional to 420.35, 627.69 and 343.46

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Solution

The fourth proportional to 420.35, 627.69 and 343.46 is: 512.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.35 : 627.69 = 343.46 : x
  2. Step 2: Convert to fraction form
    420.35/627.69 = 343.46/x
  3. Step 3: Cross multiply
    420.35x = 627.69 × 343.46
  4. Step 4: Simplify right side
    420.35x = 215,586.41
  5. Step 5: Solve for x
    x = 215,586.41/420.35
  6. Step 6: Final answer
    x = 512.87

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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.