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Finding the Fourth Proportional to 499.40, 749.10 and 280.70

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Solution

The fourth proportional to 499.40, 749.10 and 280.70 is: 421.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.40 : 749.10 = 280.70 : x
  2. Step 2: Convert to fraction form
    499.40/749.10 = 280.70/x
  3. Step 3: Cross multiply
    499.40x = 749.10 × 280.70
  4. Step 4: Simplify right side
    499.40x = 210,272.37
  5. Step 5: Solve for x
    x = 210,272.37/499.40
  6. Step 6: Final answer
    x = 421.05

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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.