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Finding the Fourth Proportional to 720.72, 1,080.14 and 287.37

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Solution

The fourth proportional to 720.72, 1,080.14 and 287.37 is: 430.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.72 : 1,080.14 = 287.37 : x
  2. Step 2: Convert to fraction form
    720.72/1,080.14 = 287.37/x
  3. Step 3: Cross multiply
    720.72x = 1,080.14 × 287.37
  4. Step 4: Simplify right side
    720.72x = 310,398.39
  5. Step 5: Solve for x
    x = 310,398.39/720.72
  6. Step 6: Final answer
    x = 430.68

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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.