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Finding the Fourth Proportional to 638.51, 880.53 and 386.39

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Solution

The fourth proportional to 638.51, 880.53 and 386.39 is: 532.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.51 : 880.53 = 386.39 : x
  2. Step 2: Convert to fraction form
    638.51/880.53 = 386.39/x
  3. Step 3: Cross multiply
    638.51x = 880.53 × 386.39
  4. Step 4: Simplify right side
    638.51x = 340,230.19
  5. Step 5: Solve for x
    x = 340,230.19/638.51
  6. Step 6: Final answer
    x = 532.85

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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.