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Finding the Fourth Proportional to 210.90, 290.69 and 171.72

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Solution

The fourth proportional to 210.90, 290.69 and 171.72 is: 236.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.90 : 290.69 = 171.72 : x
  2. Step 2: Convert to fraction form
    210.90/290.69 = 171.72/x
  3. Step 3: Cross multiply
    210.90x = 290.69 × 171.72
  4. Step 4: Simplify right side
    210.90x = 49,917.07
  5. Step 5: Solve for x
    x = 49,917.07/210.90
  6. Step 6: Final answer
    x = 236.68

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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.