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Finding the Fourth Proportional to 315.87, 435.66 and 280.47

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Solution

The fourth proportional to 315.87, 435.66 and 280.47 is: 386.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.87 : 435.66 = 280.47 : x
  2. Step 2: Convert to fraction form
    315.87/435.66 = 280.47/x
  3. Step 3: Cross multiply
    315.87x = 435.66 × 280.47
  4. Step 4: Simplify right side
    315.87x = 122,189.56
  5. Step 5: Solve for x
    x = 122,189.56/315.87
  6. Step 6: Final answer
    x = 386.83

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.