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Finding the Fourth Proportional to 720.54, 1,081.08 and 258.30

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Solution

The fourth proportional to 720.54, 1,081.08 and 258.30 is: 387.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.54 : 1,081.08 = 258.30 : x
  2. Step 2: Convert to fraction form
    720.54/1,081.08 = 258.30/x
  3. Step 3: Cross multiply
    720.54x = 1,081.08 × 258.30
  4. Step 4: Simplify right side
    720.54x = 279,242.96
  5. Step 5: Solve for x
    x = 279,242.96/720.54
  6. Step 6: Final answer
    x = 387.55

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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.