Home / 654.11-981.16-221.25

Finding the Fourth Proportional to 654.11, 981.16 and 221.25

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Solution

The fourth proportional to 654.11, 981.16 and 221.25 is: 331.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.11 : 981.16 = 221.25 : x
  2. Step 2: Convert to fraction form
    654.11/981.16 = 221.25/x
  3. Step 3: Cross multiply
    654.11x = 981.16 × 221.25
  4. Step 4: Simplify right side
    654.11x = 217,081.10
  5. Step 5: Solve for x
    x = 217,081.10/654.11
  6. Step 6: Final answer
    x = 331.88

Related Problems

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Double scale
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Similar ratio
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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.