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Finding the Third Proportional to 280.50 and 378.75

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Solution

The third proportional to 280.50 and 378.75 is: 511.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.50 : 378.75 = 378.75 : x
  2. Step 2: Convert to fraction form
    280.50/378.75 = 378.75/x
  3. Step 3: Cross multiply
    280.50x = 378.75 × 378.75
  4. Step 4: Simplify right side
    280.50x = 143,451.56
  5. Step 5: Solve for x
    x = 143,451.56/280.50
  6. Step 6: Final answer
    x = 511.41

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Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.