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Finding the Fourth Proportional to 499.80, 749.70 and 427.80

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Solution

The fourth proportional to 499.80, 749.70 and 427.80 is: 641.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.80 : 749.70 = 427.80 : x
  2. Step 2: Convert to fraction form
    499.80/749.70 = 427.80/x
  3. Step 3: Cross multiply
    499.80x = 749.70 × 427.80
  4. Step 4: Simplify right side
    499.80x = 320,721.66
  5. Step 5: Solve for x
    x = 320,721.66/499.80
  6. Step 6: Final answer
    x = 641.70

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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.