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Finding the Fourth Proportional to 631.66, 871.71 and 351.90

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Solution

The fourth proportional to 631.66, 871.71 and 351.90 is: 485.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.66 : 871.71 = 351.90 : x
  2. Step 2: Convert to fraction form
    631.66/871.71 = 351.90/x
  3. Step 3: Cross multiply
    631.66x = 871.71 × 351.90
  4. Step 4: Simplify right side
    631.66x = 306,754.75
  5. Step 5: Solve for x
    x = 306,754.75/631.66
  6. Step 6: Final answer
    x = 485.63

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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.