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Finding the Fourth Proportional to 280.21, 418.34 and 214.87

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Solution

The fourth proportional to 280.21, 418.34 and 214.87 is: 320.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.21 : 418.34 = 214.87 : x
  2. Step 2: Convert to fraction form
    280.21/418.34 = 214.87/x
  3. Step 3: Cross multiply
    280.21x = 418.34 × 214.87
  4. Step 4: Simplify right side
    280.21x = 89,888.72
  5. Step 5: Solve for x
    x = 89,888.72/280.21
  6. Step 6: Final answer
    x = 320.79

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.