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Finding the Fourth Proportional to 720.14, 1,080.28 and 258.18

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Solution

The fourth proportional to 720.14, 1,080.28 and 258.18 is: 387.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.14 : 1,080.28 = 258.18 : x
  2. Step 2: Convert to fraction form
    720.14/1,080.28 = 258.18/x
  3. Step 3: Cross multiply
    720.14x = 1,080.28 × 258.18
  4. Step 4: Simplify right side
    720.14x = 278,906.69
  5. Step 5: Solve for x
    x = 278,906.69/720.14
  6. Step 6: Final answer
    x = 387.30

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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.