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Finding the Fourth Proportional to 878.27, 1,212 and 485.29

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Solution

The fourth proportional to 878.27, 1,212 and 485.29 is: 669.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    878.27 : 1,212 = 485.29 : x
  2. Step 2: Convert to fraction form
    878.27/1,212 = 485.29/x
  3. Step 3: Cross multiply
    878.27x = 1,212 × 485.29
  4. Step 4: Simplify right side
    878.27x = 588,165.42
  5. Step 5: Solve for x
    x = 588,165.42/878.27
  6. Step 6: Final answer
    x = 669.69

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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.