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Finding the Fourth Proportional to 654.28, 981.38 and 631.21

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Solution

The fourth proportional to 654.28, 981.38 and 631.21 is: 946.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.28 : 981.38 = 631.21 : x
  2. Step 2: Convert to fraction form
    654.28/981.38 = 631.21/x
  3. Step 3: Cross multiply
    654.28x = 981.38 × 631.21
  4. Step 4: Simplify right side
    654.28x = 619,451.96
  5. Step 5: Solve for x
    x = 619,451.96/654.28
  6. Step 6: Final answer
    x = 946.78

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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.