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Finding the Fourth Proportional to 647.28, 971.28 and 262.80

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Solution

The fourth proportional to 647.28, 971.28 and 262.80 is: 394.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.28 : 971.28 = 262.80 : x
  2. Step 2: Convert to fraction form
    647.28/971.28 = 262.80/x
  3. Step 3: Cross multiply
    647.28x = 971.28 × 262.80
  4. Step 4: Simplify right side
    647.28x = 255,252.38
  5. Step 5: Solve for x
    x = 255,252.38/647.28
  6. Step 6: Final answer
    x = 394.35

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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.