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Finding the Fourth Proportional to 638.49, 956.81 and 345.74

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Solution

The fourth proportional to 638.49, 956.81 and 345.74 is: 518.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.49 : 956.81 = 345.74 : x
  2. Step 2: Convert to fraction form
    638.49/956.81 = 345.74/x
  3. Step 3: Cross multiply
    638.49x = 956.81 × 345.74
  4. Step 4: Simplify right side
    638.49x = 330,808.15
  5. Step 5: Solve for x
    x = 330,808.15/638.49
  6. Step 6: Final answer
    x = 518.11

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.