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Finding the Fourth Proportional to 618.28, 854.20 and 485.96

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Solution

The fourth proportional to 618.28, 854.20 and 485.96 is: 671.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.28 : 854.20 = 485.96 : x
  2. Step 2: Convert to fraction form
    618.28/854.20 = 485.96/x
  3. Step 3: Cross multiply
    618.28x = 854.20 × 485.96
  4. Step 4: Simplify right side
    618.28x = 415,107.03
  5. Step 5: Solve for x
    x = 415,107.03/618.28
  6. Step 6: Final answer
    x = 671.39

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Half scale
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Double scale
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Similar ratio
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1.5x scale

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.