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Finding the Fourth Proportional to 479.88, 720.63 and 427.91

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Solution

The fourth proportional to 479.88, 720.63 and 427.91 is: 642.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.88 : 720.63 = 427.91 : x
  2. Step 2: Convert to fraction form
    479.88/720.63 = 427.91/x
  3. Step 3: Cross multiply
    479.88x = 720.63 × 427.91
  4. Step 4: Simplify right side
    479.88x = 308,361.18
  5. Step 5: Solve for x
    x = 308,361.18/479.88
  6. Step 6: Final answer
    x = 642.58

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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.