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Finding the Fourth Proportional to 486.84, 671.70 and 290.20

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Solution

The fourth proportional to 486.84, 671.70 and 290.20 is: 400.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.84 : 671.70 = 290.20 : x
  2. Step 2: Convert to fraction form
    486.84/671.70 = 290.20/x
  3. Step 3: Cross multiply
    486.84x = 671.70 × 290.20
  4. Step 4: Simplify right side
    486.84x = 194,927.34
  5. Step 5: Solve for x
    x = 194,927.34/486.84
  6. Step 6: Final answer
    x = 400.39

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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.