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Finding the Third Proportional to 14 and 21

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Solution

The third proportional to 14 and 21 is: 31.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    14 : 21 = 21 : x
  2. Step 2: Convert to fraction form
    14/21 = 21/x
  3. Step 3: Cross multiply
    14x = 21 × 21
  4. Step 4: Simplify right side
    14x = 441
  5. Step 5: Solve for x
    x = 441/14
  6. Step 6: Final answer
    x = 31.50

Related Problems

Find third proportional to 7 and 10.50
Half scale
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Double scale
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Similar ratio
Find third proportional to 21 and 31.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.