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Finding the Fourth Proportional to 401.09, 553.57 and 387.59

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Solution

The fourth proportional to 401.09, 553.57 and 387.59 is: 534.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.09 : 553.57 = 387.59 : x
  2. Step 2: Convert to fraction form
    401.09/553.57 = 387.59/x
  3. Step 3: Cross multiply
    401.09x = 553.57 × 387.59
  4. Step 4: Simplify right side
    401.09x = 214,554.46
  5. Step 5: Solve for x
    x = 214,554.46/401.09
  6. Step 6: Final answer
    x = 534.94

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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.