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Finding the Fourth Proportional to 290.09, 400.25 and 172.05

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Solution

The fourth proportional to 290.09, 400.25 and 172.05 is: 237.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.09 : 400.25 = 172.05 : x
  2. Step 2: Convert to fraction form
    290.09/400.25 = 172.05/x
  3. Step 3: Cross multiply
    290.09x = 400.25 × 172.05
  4. Step 4: Simplify right side
    290.09x = 68,862.15
  5. Step 5: Solve for x
    x = 68,862.15/290.09
  6. Step 6: Final answer
    x = 237.39

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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.