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Finding the Fourth Proportional to 800.21, 1,200.99 and 313.60

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Solution

The fourth proportional to 800.21, 1,200.99 and 313.60 is: 470.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.21 : 1,200.99 = 313.60 : x
  2. Step 2: Convert to fraction form
    800.21/1,200.99 = 313.60/x
  3. Step 3: Cross multiply
    800.21x = 1,200.99 × 313.60
  4. Step 4: Simplify right side
    800.21x = 376,624.46
  5. Step 5: Solve for x
    x = 376,624.46/800.21
  6. Step 6: Final answer
    x = 470.66

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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.