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Finding the Fourth Proportional to 631.78, 871.72 and 383.05

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Solution

The fourth proportional to 631.78, 871.72 and 383.05 is: 528.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.78 : 871.72 = 383.05 : x
  2. Step 2: Convert to fraction form
    631.78/871.72 = 383.05/x
  3. Step 3: Cross multiply
    631.78x = 871.72 × 383.05
  4. Step 4: Simplify right side
    631.78x = 333,906.07
  5. Step 5: Solve for x
    x = 333,906.07/631.78
  6. Step 6: Final answer
    x = 528.52

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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.