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Finding the Fourth Proportional to 515.80, 774.30 and 272.20

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Solution

The fourth proportional to 515.80, 774.30 and 272.20 is: 408.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.80 : 774.30 = 272.20 : x
  2. Step 2: Convert to fraction form
    515.80/774.30 = 272.20/x
  3. Step 3: Cross multiply
    515.80x = 774.30 × 272.20
  4. Step 4: Simplify right side
    515.80x = 210,764.46
  5. Step 5: Solve for x
    x = 210,764.46/515.80
  6. Step 6: Final answer
    x = 408.62

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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.