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Finding the Third Proportional to 100 and 121

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Solution

The third proportional to 100 and 121 is: 146.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    100 : 121 = 121 : x
  2. Step 2: Convert to fraction form
    100/121 = 121/x
  3. Step 3: Cross multiply
    100x = 121 × 121
  4. Step 4: Simplify right side
    100x = 14,641
  5. Step 5: Solve for x
    x = 14,641/100
  6. Step 6: Final answer
    x = 146.41

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Why These Related Problems?

These problems maintain the same ratio (1.21) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.