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Finding the Third Proportional to 278 and 391.50

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Solution

The third proportional to 278 and 391.50 is: 551.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    278 : 391.50 = 391.50 : x
  2. Step 2: Convert to fraction form
    278/391.50 = 391.50/x
  3. Step 3: Cross multiply
    278x = 391.50 × 391.50
  4. Step 4: Simplify right side
    278x = 153,272.25
  5. Step 5: Solve for x
    x = 153,272.25/278
  6. Step 6: Final answer
    x = 551.34

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These problems maintain the same ratio (1.41) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.