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Finding the Fourth Proportional to 415.80, 623.73 and 172.29

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Solution

The fourth proportional to 415.80, 623.73 and 172.29 is: 258.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.80 : 623.73 = 172.29 : x
  2. Step 2: Convert to fraction form
    415.80/623.73 = 172.29/x
  3. Step 3: Cross multiply
    415.80x = 623.73 × 172.29
  4. Step 4: Simplify right side
    415.80x = 107,462.44
  5. Step 5: Solve for x
    x = 107,462.44/415.80
  6. Step 6: Final answer
    x = 258.45

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.