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Finding the Fourth Proportional to 491.75, 678.66 and 281.99

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Solution

The fourth proportional to 491.75, 678.66 and 281.99 is: 389.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.75 : 678.66 = 281.99 : x
  2. Step 2: Convert to fraction form
    491.75/678.66 = 281.99/x
  3. Step 3: Cross multiply
    491.75x = 678.66 × 281.99
  4. Step 4: Simplify right side
    491.75x = 191,375.33
  5. Step 5: Solve for x
    x = 191,375.33/491.75
  6. Step 6: Final answer
    x = 389.17

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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.