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Finding the Fourth Proportional to 280.69, 421.30 and 136.51

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Solution

The fourth proportional to 280.69, 421.30 and 136.51 is: 204.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.69 : 421.30 = 136.51 : x
  2. Step 2: Convert to fraction form
    280.69/421.30 = 136.51/x
  3. Step 3: Cross multiply
    280.69x = 421.30 × 136.51
  4. Step 4: Simplify right side
    280.69x = 57,511.66
  5. Step 5: Solve for x
    x = 57,511.66/280.69
  6. Step 6: Final answer
    x = 204.89

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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.