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Finding the Fourth Proportional to 631.50, 871.50 and 351.78

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Solution

The fourth proportional to 631.50, 871.50 and 351.78 is: 485.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.50 : 871.50 = 351.78 : x
  2. Step 2: Convert to fraction form
    631.50/871.50 = 351.78/x
  3. Step 3: Cross multiply
    631.50x = 871.50 × 351.78
  4. Step 4: Simplify right side
    631.50x = 306,576.27
  5. Step 5: Solve for x
    x = 306,576.27/631.50
  6. Step 6: Final answer
    x = 485.47

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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.