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Finding the Fourth Proportional to 318.80, 439.89 and 187.81

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Solution

The fourth proportional to 318.80, 439.89 and 187.81 is: 259.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    318.80 : 439.89 = 187.81 : x
  2. Step 2: Convert to fraction form
    318.80/439.89 = 187.81/x
  3. Step 3: Cross multiply
    318.80x = 439.89 × 187.81
  4. Step 4: Simplify right side
    318.80x = 82,615.74
  5. Step 5: Solve for x
    x = 82,615.74/318.80
  6. Step 6: Final answer
    x = 259.15

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.