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Finding the Fourth Proportional to 207.22, 285.96 and 128.51

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Solution

The fourth proportional to 207.22, 285.96 and 128.51 is: 177.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    207.22 : 285.96 = 128.51 : x
  2. Step 2: Convert to fraction form
    207.22/285.96 = 128.51/x
  3. Step 3: Cross multiply
    207.22x = 285.96 × 128.51
  4. Step 4: Simplify right side
    207.22x = 36,748.04
  5. Step 5: Solve for x
    x = 36,748.04/207.22
  6. Step 6: Final answer
    x = 177.34

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.