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Finding the Fourth Proportional to 495.20, 678.84 and 486.36

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Solution

The fourth proportional to 495.20, 678.84 and 486.36 is: 666.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    495.20 : 678.84 = 486.36 : x
  2. Step 2: Convert to fraction form
    495.20/678.84 = 486.36/x
  3. Step 3: Cross multiply
    495.20x = 678.84 × 486.36
  4. Step 4: Simplify right side
    495.20x = 330,160.62
  5. Step 5: Solve for x
    x = 330,160.62/495.20
  6. Step 6: Final answer
    x = 666.73

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.