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Finding the Fourth Proportional to 688.25, 1,030.82 and 665.19

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Solution

The fourth proportional to 688.25, 1,030.82 and 665.19 is: 996.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.25 : 1,030.82 = 665.19 : x
  2. Step 2: Convert to fraction form
    688.25/1,030.82 = 665.19/x
  3. Step 3: Cross multiply
    688.25x = 1,030.82 × 665.19
  4. Step 4: Simplify right side
    688.25x = 685,687.83
  5. Step 5: Solve for x
    x = 685,687.83/688.25
  6. Step 6: Final answer
    x = 996.27

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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.