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Finding the Fourth Proportional to 401.78, 602.69 and 127.80

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Solution

The fourth proportional to 401.78, 602.69 and 127.80 is: 191.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.78 : 602.69 = 127.80 : x
  2. Step 2: Convert to fraction form
    401.78/602.69 = 127.80/x
  3. Step 3: Cross multiply
    401.78x = 602.69 × 127.80
  4. Step 4: Simplify right side
    401.78x = 77,023.14
  5. Step 5: Solve for x
    x = 77,023.14/401.78
  6. Step 6: Final answer
    x = 191.71

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.