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Finding the Fourth Proportional to 280.70, 387.05 and 205.67

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Solution

The fourth proportional to 280.70, 387.05 and 205.67 is: 283.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.70 : 387.05 = 205.67 : x
  2. Step 2: Convert to fraction form
    280.70/387.05 = 205.67/x
  3. Step 3: Cross multiply
    280.70x = 387.05 × 205.67
  4. Step 4: Simplify right side
    280.70x = 79,601.61
  5. Step 5: Solve for x
    x = 79,601.61/280.70
  6. Step 6: Final answer
    x = 283.59

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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.