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Finding the Fourth Proportional to 486.81, 671.81 and 279.81

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Solution

The fourth proportional to 486.81, 671.81 and 279.81 is: 386.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.81 : 671.81 = 279.81 : x
  2. Step 2: Convert to fraction form
    486.81/671.81 = 279.81/x
  3. Step 3: Cross multiply
    486.81x = 671.81 × 279.81
  4. Step 4: Simplify right side
    486.81x = 187,979.16
  5. Step 5: Solve for x
    x = 187,979.16/486.81
  6. Step 6: Final answer
    x = 386.14

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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.