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Finding the Third Proportional to 280 and 387.50

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Solution

The third proportional to 280 and 387.50 is: 536.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    280 : 387.50 = 387.50 : x
  2. Step 2: Convert to fraction form
    280/387.50 = 387.50/x
  3. Step 3: Cross multiply
    280x = 387.50 × 387.50
  4. Step 4: Simplify right side
    280x = 150,156.25
  5. Step 5: Solve for x
    x = 150,156.25/280
  6. Step 6: Final answer
    x = 536.27

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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.