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Finding the Fourth Proportional to 631.36, 871.32 and 491.25

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Solution

The fourth proportional to 631.36, 871.32 and 491.25 is: 677.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.36 : 871.32 = 491.25 : x
  2. Step 2: Convert to fraction form
    631.36/871.32 = 491.25/x
  3. Step 3: Cross multiply
    631.36x = 871.32 × 491.25
  4. Step 4: Simplify right side
    631.36x = 428,035.95
  5. Step 5: Solve for x
    x = 428,035.95/631.36
  6. Step 6: Final answer
    x = 677.96

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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.