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Finding the Fourth Proportional to 631.65, 871.65 and 351.91

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Solution

The fourth proportional to 631.65, 871.65 and 351.91 is: 485.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.65 : 871.65 = 351.91 : x
  2. Step 2: Convert to fraction form
    631.65/871.65 = 351.91/x
  3. Step 3: Cross multiply
    631.65x = 871.65 × 351.91
  4. Step 4: Simplify right side
    631.65x = 306,745.23
  5. Step 5: Solve for x
    x = 306,745.23/631.65
  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.