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Finding the Fourth Proportional to 640.13, 882.87 and 378.14

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Solution

The fourth proportional to 640.13, 882.87 and 378.14 is: 521.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.13 : 882.87 = 378.14 : x
  2. Step 2: Convert to fraction form
    640.13/882.87 = 378.14/x
  3. Step 3: Cross multiply
    640.13x = 882.87 × 378.14
  4. Step 4: Simplify right side
    640.13x = 333,848.46
  5. Step 5: Solve for x
    x = 333,848.46/640.13
  6. Step 6: Final answer
    x = 521.53

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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.