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Finding the Fourth Proportional to 631.78, 947.51 and 220.85

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Solution

The fourth proportional to 631.78, 947.51 and 220.85 is: 331.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.78 : 947.51 = 220.85 : x
  2. Step 2: Convert to fraction form
    631.78/947.51 = 220.85/x
  3. Step 3: Cross multiply
    631.78x = 947.51 × 220.85
  4. Step 4: Simplify right side
    631.78x = 209,257.58
  5. Step 5: Solve for x
    x = 209,257.58/631.78
  6. Step 6: Final answer
    x = 331.22

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.