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Finding the Fourth Proportional to 645.93, 969.84 and 280.98

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Solution

The fourth proportional to 645.93, 969.84 and 280.98 is: 421.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.93 : 969.84 = 280.98 : x
  2. Step 2: Convert to fraction form
    645.93/969.84 = 280.98/x
  3. Step 3: Cross multiply
    645.93x = 969.84 × 280.98
  4. Step 4: Simplify right side
    645.93x = 272,505.64
  5. Step 5: Solve for x
    x = 272,505.64/645.93
  6. Step 6: Final answer
    x = 421.88

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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.