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Finding the Fourth Proportional to 631.28, 947.28 and 438.32

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Solution

The fourth proportional to 631.28, 947.28 and 438.32 is: 657.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.28 : 947.28 = 438.32 : x
  2. Step 2: Convert to fraction form
    631.28/947.28 = 438.32/x
  3. Step 3: Cross multiply
    631.28x = 947.28 × 438.32
  4. Step 4: Simplify right side
    631.28x = 415,211.77
  5. Step 5: Solve for x
    x = 415,211.77/631.28
  6. Step 6: Final answer
    x = 657.73

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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.