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Finding the Fourth Proportional to 280.56, 420.36 and 172.44

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Solution

The fourth proportional to 280.56, 420.36 and 172.44 is: 258.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.56 : 420.36 = 172.44 : x
  2. Step 2: Convert to fraction form
    280.56/420.36 = 172.44/x
  3. Step 3: Cross multiply
    280.56x = 420.36 × 172.44
  4. Step 4: Simplify right side
    280.56x = 72,486.88
  5. Step 5: Solve for x
    x = 72,486.88/280.56
  6. Step 6: Final answer
    x = 258.36

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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.