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Finding the Fourth Proportional to 319.80, 478.56 and 189.87

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Solution

The fourth proportional to 319.80, 478.56 and 189.87 is: 284.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.80 : 478.56 = 189.87 : x
  2. Step 2: Convert to fraction form
    319.80/478.56 = 189.87/x
  3. Step 3: Cross multiply
    319.80x = 478.56 × 189.87
  4. Step 4: Simplify right side
    319.80x = 90,863.24
  5. Step 5: Solve for x
    x = 90,863.24/319.80
  6. Step 6: Final answer
    x = 284.13

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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.