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Finding the Fourth Proportional to 210.78, 290.85 and 123.44

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Solution

The fourth proportional to 210.78, 290.85 and 123.44 is: 170.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.78 : 290.85 = 123.44 : x
  2. Step 2: Convert to fraction form
    210.78/290.85 = 123.44/x
  3. Step 3: Cross multiply
    210.78x = 290.85 × 123.44
  4. Step 4: Simplify right side
    210.78x = 35,902.52
  5. Step 5: Solve for x
    x = 35,902.52/210.78
  6. Step 6: Final answer
    x = 170.33

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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.