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Finding the Fourth Proportional to 479.80, 719.96 and 260.20

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Solution

The fourth proportional to 479.80, 719.96 and 260.20 is: 390.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.80 : 719.96 = 260.20 : x
  2. Step 2: Convert to fraction form
    479.80/719.96 = 260.20/x
  3. Step 3: Cross multiply
    479.80x = 719.96 × 260.20
  4. Step 4: Simplify right side
    479.80x = 187,333.59
  5. Step 5: Solve for x
    x = 187,333.59/479.80
  6. Step 6: Final answer
    x = 390.44

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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.