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Finding the Third Proportional to 311 and 480

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Solution

The third proportional to 311 and 480 is: 740.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    311 : 480 = 480 : x
  2. Step 2: Convert to fraction form
    311/480 = 480/x
  3. Step 3: Cross multiply
    311x = 480 × 480
  4. Step 4: Simplify right side
    311x = 230,400
  5. Step 5: Solve for x
    x = 230,400/311
  6. Step 6: Final answer
    x = 740.84

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These problems maintain the same ratio (1.54) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.