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Finding the Fourth Proportional to 517.10, 779.18 and 427.80

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Solution

The fourth proportional to 517.10, 779.18 and 427.80 is: 644.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    517.10 : 779.18 = 427.80 : x
  2. Step 2: Convert to fraction form
    517.10/779.18 = 427.80/x
  3. Step 3: Cross multiply
    517.10x = 779.18 × 427.80
  4. Step 4: Simplify right side
    517.10x = 333,333.20
  5. Step 5: Solve for x
    x = 333,333.20/517.10
  6. Step 6: Final answer
    x = 644.62

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.