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Finding the Fourth Proportional to 628.45, 868.39 and 488.93

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Solution

The fourth proportional to 628.45, 868.39 and 488.93 is: 675.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.45 : 868.39 = 488.93 : x
  2. Step 2: Convert to fraction form
    628.45/868.39 = 488.93/x
  3. Step 3: Cross multiply
    628.45x = 868.39 × 488.93
  4. Step 4: Simplify right side
    628.45x = 424,576.36
  5. Step 5: Solve for x
    x = 424,576.36/628.45
  6. Step 6: Final answer
    x = 675.60

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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.