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Finding the Fourth Proportional to 319.80, 479.64 and 259.68

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Solution

The fourth proportional to 319.80, 479.64 and 259.68 is: 389.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.80 : 479.64 = 259.68 : x
  2. Step 2: Convert to fraction form
    319.80/479.64 = 259.68/x
  3. Step 3: Cross multiply
    319.80x = 479.64 × 259.68
  4. Step 4: Simplify right side
    319.80x = 124,552.92
  5. Step 5: Solve for x
    x = 124,552.92/319.80
  6. Step 6: Final answer
    x = 389.47

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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.