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Finding the Fourth Proportional to 479.85, 720.18 and 206.15

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Solution

The fourth proportional to 479.85, 720.18 and 206.15 is: 309.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.85 : 720.18 = 206.15 : x
  2. Step 2: Convert to fraction form
    479.85/720.18 = 206.15/x
  3. Step 3: Cross multiply
    479.85x = 720.18 × 206.15
  4. Step 4: Simplify right side
    479.85x = 148,461.51
  5. Step 5: Solve for x
    x = 148,461.51/479.85
  6. Step 6: Final answer
    x = 309.39

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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.