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Finding the Fourth Proportional to 287.76, 399.27 and 276.20

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Solution

The fourth proportional to 287.76, 399.27 and 276.20 is: 383.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.76 : 399.27 = 276.20 : x
  2. Step 2: Convert to fraction form
    287.76/399.27 = 276.20/x
  3. Step 3: Cross multiply
    287.76x = 399.27 × 276.20
  4. Step 4: Simplify right side
    287.76x = 110,276.38
  5. Step 5: Solve for x
    x = 110,276.38/287.76
  6. Step 6: Final answer
    x = 383.22

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.