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Finding the Fourth Proportional to 486.90, 671.88 and 290.37

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Solution

The fourth proportional to 486.90, 671.88 and 290.37 is: 400.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.90 : 671.88 = 290.37 : x
  2. Step 2: Convert to fraction form
    486.90/671.88 = 290.37/x
  3. Step 3: Cross multiply
    486.90x = 671.88 × 290.37
  4. Step 4: Simplify right side
    486.90x = 195,093.80
  5. Step 5: Solve for x
    x = 195,093.80/486.90
  6. Step 6: Final answer
    x = 400.69

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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.