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Finding the Fourth Proportional to 710.40, 979.20 and 579.20

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Solution

The fourth proportional to 710.40, 979.20 and 579.20 is: 798.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    710.40 : 979.20 = 579.20 : x
  2. Step 2: Convert to fraction form
    710.40/979.20 = 579.20/x
  3. Step 3: Cross multiply
    710.40x = 979.20 × 579.20
  4. Step 4: Simplify right side
    710.40x = 567,152.64
  5. Step 5: Solve for x
    x = 567,152.64/710.40
  6. Step 6: Final answer
    x = 798.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.