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Finding the Fourth Proportional to 486.35, 728.10 and 378.21

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Solution

The fourth proportional to 486.35, 728.10 and 378.21 is: 566.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.35 : 728.10 = 378.21 : x
  2. Step 2: Convert to fraction form
    486.35/728.10 = 378.21/x
  3. Step 3: Cross multiply
    486.35x = 728.10 × 378.21
  4. Step 4: Simplify right side
    486.35x = 275,377.47
  5. Step 5: Solve for x
    x = 275,377.47/486.35
  6. Step 6: Final answer
    x = 566.22

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.