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Finding the Fourth Proportional to 631.20, 870.96 and 351.42

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Solution

The fourth proportional to 631.20, 870.96 and 351.42 is: 484.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.20 : 870.96 = 351.42 : x
  2. Step 2: Convert to fraction form
    631.20/870.96 = 351.42/x
  3. Step 3: Cross multiply
    631.20x = 870.96 × 351.42
  4. Step 4: Simplify right side
    631.20x = 306,072.76
  5. Step 5: Solve for x
    x = 306,072.76/631.20
  6. Step 6: Final answer
    x = 484.91

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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.