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Finding the Fourth Proportional to 480.40, 720.78 and 172.24

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Solution

The fourth proportional to 480.40, 720.78 and 172.24 is: 258.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    480.40 : 720.78 = 172.24 : x
  2. Step 2: Convert to fraction form
    480.40/720.78 = 172.24/x
  3. Step 3: Cross multiply
    480.40x = 720.78 × 172.24
  4. Step 4: Simplify right side
    480.40x = 124,147.15
  5. Step 5: Solve for x
    x = 124,147.15/480.40
  6. Step 6: Final answer
    x = 258.42

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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.