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Finding the Fourth Proportional to 319.79, 479.30 and 146.21

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Solution

The fourth proportional to 319.79, 479.30 and 146.21 is: 219.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.79 : 479.30 = 146.21 : x
  2. Step 2: Convert to fraction form
    319.79/479.30 = 146.21/x
  3. Step 3: Cross multiply
    319.79x = 479.30 × 146.21
  4. Step 4: Simplify right side
    319.79x = 70,078.92
  5. Step 5: Solve for x
    x = 70,078.92/319.79
  6. Step 6: Final answer
    x = 219.14

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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.