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Finding the Third Proportional to 291 and 318

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Solution

The third proportional to 291 and 318 is: 347.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    291 : 318 = 318 : x
  2. Step 2: Convert to fraction form
    291/318 = 318/x
  3. Step 3: Cross multiply
    291x = 318 × 318
  4. Step 4: Simplify right side
    291x = 101,124
  5. Step 5: Solve for x
    x = 101,124/291
  6. Step 6: Final answer
    x = 347.51

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Why These Related Problems?

These problems maintain the same ratio (1.09) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.