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Finding the Fourth Proportional to 479.52, 720 and 388.80

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Solution

The fourth proportional to 479.52, 720 and 388.80 is: 583.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.52 : 720 = 388.80 : x
  2. Step 2: Convert to fraction form
    479.52/720 = 388.80/x
  3. Step 3: Cross multiply
    479.52x = 720 × 388.80
  4. Step 4: Simplify right side
    479.52x = 279,936
  5. Step 5: Solve for x
    x = 279,936/479.52
  6. Step 6: Final answer
    x = 583.78

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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.