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Finding the Fourth Proportional to 618.39, 853.67 and 397.71

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Solution

The fourth proportional to 618.39, 853.67 and 397.71 is: 549.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.39 : 853.67 = 397.71 : x
  2. Step 2: Convert to fraction form
    618.39/853.67 = 397.71/x
  3. Step 3: Cross multiply
    618.39x = 853.67 × 397.71
  4. Step 4: Simplify right side
    618.39x = 339,511.11
  5. Step 5: Solve for x
    x = 339,511.11/618.39
  6. Step 6: Final answer
    x = 549.03

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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.