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Finding the Third Proportional to 315 and 354

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Solution

The third proportional to 315 and 354 is: 397.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    315 : 354 = 354 : x
  2. Step 2: Convert to fraction form
    315/354 = 354/x
  3. Step 3: Cross multiply
    315x = 354 × 354
  4. Step 4: Simplify right side
    315x = 125,316
  5. Step 5: Solve for x
    x = 125,316/315
  6. Step 6: Final answer
    x = 397.83

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Why These Related Problems?

These problems maintain the same ratio (1.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.