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Finding the Third Proportional to 7.78 and 15.56

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Solution

The third proportional to 7.78 and 15.56 is: 31.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.78 : 15.56 = 15.56 : x
  2. Step 2: Convert to fraction form
    7.78/15.56 = 15.56/x
  3. Step 3: Cross multiply
    7.78x = 15.56 × 15.56
  4. Step 4: Simplify right side
    7.78x = 242.19
  5. Step 5: Solve for x
    x = 242.19/7.78
  6. Step 6: Final answer
    x = 31.13

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.