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Finding the Fourth Proportional to 643.38, 887.86 and 348.65

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Solution

The fourth proportional to 643.38, 887.86 and 348.65 is: 481.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.38 : 887.86 = 348.65 : x
  2. Step 2: Convert to fraction form
    643.38/887.86 = 348.65/x
  3. Step 3: Cross multiply
    643.38x = 887.86 × 348.65
  4. Step 4: Simplify right side
    643.38x = 309,552.39
  5. Step 5: Solve for x
    x = 309,552.39/643.38
  6. Step 6: Final answer
    x = 481.13

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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.