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Finding the Fourth Proportional to 654.21, 981.01 and 221.06

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Solution

The fourth proportional to 654.21, 981.01 and 221.06 is: 331.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.21 : 981.01 = 221.06 : x
  2. Step 2: Convert to fraction form
    654.21/981.01 = 221.06/x
  3. Step 3: Cross multiply
    654.21x = 981.01 × 221.06
  4. Step 4: Simplify right side
    654.21x = 216,864.80
  5. Step 5: Solve for x
    x = 216,864.80/654.21
  6. Step 6: Final answer
    x = 331.49

Related Problems

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Double scale
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Similar ratio
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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.