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Finding the Fourth Proportional to 207.15, 285.79 and 119.80

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Solution

The fourth proportional to 207.15, 285.79 and 119.80 is: 165.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    207.15 : 285.79 = 119.80 : x
  2. Step 2: Convert to fraction form
    207.15/285.79 = 119.80/x
  3. Step 3: Cross multiply
    207.15x = 285.79 × 119.80
  4. Step 4: Simplify right side
    207.15x = 34,237.64
  5. Step 5: Solve for x
    x = 34,237.64/207.15
  6. Step 6: Final answer
    x = 165.28

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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.