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Finding the Fourth Proportional to 628.72, 867 and 485.08

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Solution

The fourth proportional to 628.72, 867 and 485.08 is: 668.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.72 : 867 = 485.08 : x
  2. Step 2: Convert to fraction form
    628.72/867 = 485.08/x
  3. Step 3: Cross multiply
    628.72x = 867 × 485.08
  4. Step 4: Simplify right side
    628.72x = 420,564.36
  5. Step 5: Solve for x
    x = 420,564.36/628.72
  6. Step 6: Final answer
    x = 668.92

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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.