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Finding the Fourth Proportional to 491.32, 672.23 and 489.28

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Solution

The fourth proportional to 491.32, 672.23 and 489.28 is: 669.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.32 : 672.23 = 489.28 : x
  2. Step 2: Convert to fraction form
    491.32/672.23 = 489.28/x
  3. Step 3: Cross multiply
    491.32x = 672.23 × 489.28
  4. Step 4: Simplify right side
    491.32x = 328,908.69
  5. Step 5: Solve for x
    x = 328,908.69/491.32
  6. Step 6: Final answer
    x = 669.44

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.