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Finding the Fourth Proportional to 486.81, 671.76 and 290.25

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Solution

The fourth proportional to 486.81, 671.76 and 290.25 is: 400.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.81 : 671.76 = 290.25 : x
  2. Step 2: Convert to fraction form
    486.81/671.76 = 290.25/x
  3. Step 3: Cross multiply
    486.81x = 671.76 × 290.25
  4. Step 4: Simplify right side
    486.81x = 194,978.34
  5. Step 5: Solve for x
    x = 194,978.34/486.81
  6. Step 6: Final answer
    x = 400.52

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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.