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Finding the Fourth Proportional to 290.80, 401.32 and 172.86

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Solution

The fourth proportional to 290.80, 401.32 and 172.86 is: 238.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.80 : 401.32 = 172.86 : x
  2. Step 2: Convert to fraction form
    290.80/401.32 = 172.86/x
  3. Step 3: Cross multiply
    290.80x = 401.32 × 172.86
  4. Step 4: Simplify right side
    290.80x = 69,372.18
  5. Step 5: Solve for x
    x = 69,372.18/290.80
  6. Step 6: Final answer
    x = 238.56

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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.