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Finding the Fourth Proportional to 618.66, 853.08 and 485.62

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Solution

The fourth proportional to 618.66, 853.08 and 485.62 is: 669.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.66 : 853.08 = 485.62 : x
  2. Step 2: Convert to fraction form
    618.66/853.08 = 485.62/x
  3. Step 3: Cross multiply
    618.66x = 853.08 × 485.62
  4. Step 4: Simplify right side
    618.66x = 414,272.71
  5. Step 5: Solve for x
    x = 414,272.71/618.66
  6. Step 6: Final answer
    x = 669.63

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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.