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Finding the Fourth Proportional to 660.81, 909.73 and 494.81

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Solution

The fourth proportional to 660.81, 909.73 and 494.81 is: 681.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.81 : 909.73 = 494.81 : x
  2. Step 2: Convert to fraction form
    660.81/909.73 = 494.81/x
  3. Step 3: Cross multiply
    660.81x = 909.73 × 494.81
  4. Step 4: Simplify right side
    660.81x = 450,142.98
  5. Step 5: Solve for x
    x = 450,142.98/660.81
  6. Step 6: Final answer
    x = 681.20

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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.