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Finding the Fourth Proportional to 654.36, 981.38 and 221.51

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Solution

The fourth proportional to 654.36, 981.38 and 221.51 is: 332.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.36 : 981.38 = 221.51 : x
  2. Step 2: Convert to fraction form
    654.36/981.38 = 221.51/x
  3. Step 3: Cross multiply
    654.36x = 981.38 × 221.51
  4. Step 4: Simplify right side
    654.36x = 217,388.49
  5. Step 5: Solve for x
    x = 217,388.49/654.36
  6. Step 6: Final answer
    x = 332.22

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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.