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Finding the Fourth Proportional to 720.72, 1,081.08 and 658.08

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Solution

The fourth proportional to 720.72, 1,081.08 and 658.08 is: 987.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.72 : 1,081.08 = 658.08 : x
  2. Step 2: Convert to fraction form
    720.72/1,081.08 = 658.08/x
  3. Step 3: Cross multiply
    720.72x = 1,081.08 × 658.08
  4. Step 4: Simplify right side
    720.72x = 711,437.13
  5. Step 5: Solve for x
    x = 711,437.13/720.72
  6. Step 6: Final answer
    x = 987.12

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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.