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Finding the Fourth Proportional to 280.32, 420.54 and 135.84

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Solution

The fourth proportional to 280.32, 420.54 and 135.84 is: 203.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.32 : 420.54 = 135.84 : x
  2. Step 2: Convert to fraction form
    280.32/420.54 = 135.84/x
  3. Step 3: Cross multiply
    280.32x = 420.54 × 135.84
  4. Step 4: Simplify right side
    280.32x = 57,126.15
  5. Step 5: Solve for x
    x = 57,126.15/280.32
  6. Step 6: Final answer
    x = 203.79

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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.