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Finding the Third Proportional to 100 and 205

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Solution

The third proportional to 100 and 205 is: 420.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    100 : 205 = 205 : x
  2. Step 2: Convert to fraction form
    100/205 = 205/x
  3. Step 3: Cross multiply
    100x = 205 × 205
  4. Step 4: Simplify right side
    100x = 42,025
  5. Step 5: Solve for x
    x = 42,025/100
  6. Step 6: Final answer
    x = 420.25

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Why These Related Problems?

These problems maintain the same ratio (2.05) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.