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Finding the Fourth Proportional to 479.20, 718.79 and 137.20

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Solution

The fourth proportional to 479.20, 718.79 and 137.20 is: 205.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.20 : 718.79 = 137.20 : x
  2. Step 2: Convert to fraction form
    479.20/718.79 = 137.20/x
  3. Step 3: Cross multiply
    479.20x = 718.79 × 137.20
  4. Step 4: Simplify right side
    479.20x = 98,619.10
  5. Step 5: Solve for x
    x = 98,619.10/479.20
  6. Step 6: Final answer
    x = 205.80

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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.