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Finding the Fourth Proportional to 640.81, 961.26 and 479.53

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Solution

The fourth proportional to 640.81, 961.26 and 479.53 is: 719.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.81 : 961.26 = 479.53 : x
  2. Step 2: Convert to fraction form
    640.81/961.26 = 479.53/x
  3. Step 3: Cross multiply
    640.81x = 961.26 × 479.53
  4. Step 4: Simplify right side
    640.81x = 460,953.01
  5. Step 5: Solve for x
    x = 460,953.01/640.81
  6. Step 6: Final answer
    x = 719.33

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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.