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Finding the Fourth Proportional to 171.39, 256.98 and 55.78

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Solution

The fourth proportional to 171.39, 256.98 and 55.78 is: 83.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.39 : 256.98 = 55.78 : x
  2. Step 2: Convert to fraction form
    171.39/256.98 = 55.78/x
  3. Step 3: Cross multiply
    171.39x = 256.98 × 55.78
  4. Step 4: Simplify right side
    171.39x = 14,334.34
  5. Step 5: Solve for x
    x = 14,334.34/171.39
  6. Step 6: Final answer
    x = 83.64

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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.