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Finding the Fourth Proportional to 19.78, 29.80 and 17.60

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Solution

The fourth proportional to 19.78, 29.80 and 17.60 is: 26.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.78 : 29.80 = 17.60 : x
  2. Step 2: Convert to fraction form
    19.78/29.80 = 17.60/x
  3. Step 3: Cross multiply
    19.78x = 29.80 × 17.60
  4. Step 4: Simplify right side
    19.78x = 524.35
  5. Step 5: Solve for x
    x = 524.35/19.78
  6. Step 6: Final answer
    x = 26.51

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.