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Finding the Fourth Proportional to 306.39, 422.78 and 188.32

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Solution

The fourth proportional to 306.39, 422.78 and 188.32 is: 259.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.39 : 422.78 = 188.32 : x
  2. Step 2: Convert to fraction form
    306.39/422.78 = 188.32/x
  3. Step 3: Cross multiply
    306.39x = 422.78 × 188.32
  4. Step 4: Simplify right side
    306.39x = 79,617.93
  5. Step 5: Solve for x
    x = 79,617.93/306.39
  6. Step 6: Final answer
    x = 259.86

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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.