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Finding the Fourth Proportional to 280.15, 419.85 and 218.53

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Solution

The fourth proportional to 280.15, 419.85 and 218.53 is: 327.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.15 : 419.85 = 218.53 : x
  2. Step 2: Convert to fraction form
    280.15/419.85 = 218.53/x
  3. Step 3: Cross multiply
    280.15x = 419.85 × 218.53
  4. Step 4: Simplify right side
    280.15x = 91,749.82
  5. Step 5: Solve for x
    x = 91,749.82/280.15
  6. Step 6: Final answer
    x = 327.50

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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.