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Finding the Third Proportional to 315 and 355

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Solution

The third proportional to 315 and 355 is: 400.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    315 : 355 = 355 : x
  2. Step 2: Convert to fraction form
    315/355 = 355/x
  3. Step 3: Cross multiply
    315x = 355 × 355
  4. Step 4: Simplify right side
    315x = 126,025
  5. Step 5: Solve for x
    x = 126,025/315
  6. Step 6: Final answer
    x = 400.08

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Why These Related Problems?

These problems maintain the same ratio (1.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.