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Finding the Fourth Proportional to 870.81, 1,306.28 and 254.51

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Solution

The fourth proportional to 870.81, 1,306.28 and 254.51 is: 381.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.81 : 1,306.28 = 254.51 : x
  2. Step 2: Convert to fraction form
    870.81/1,306.28 = 254.51/x
  3. Step 3: Cross multiply
    870.81x = 1,306.28 × 254.51
  4. Step 4: Simplify right side
    870.81x = 332,453.52
  5. Step 5: Solve for x
    x = 332,453.52/870.81
  6. Step 6: Final answer
    x = 381.78

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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.