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Finding the Fourth Proportional to 654.30, 987.28 and 628.99

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Solution

The fourth proportional to 654.30, 987.28 and 628.99 is: 949.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.30 : 987.28 = 628.99 : x
  2. Step 2: Convert to fraction form
    654.30/987.28 = 628.99/x
  3. Step 3: Cross multiply
    654.30x = 987.28 × 628.99
  4. Step 4: Simplify right side
    654.30x = 620,989.25
  5. Step 5: Solve for x
    x = 620,989.25/654.30
  6. Step 6: Final answer
    x = 949.09

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.