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Finding the Fourth Proportional to 260.87, 389.45 and 219.86

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Solution

The fourth proportional to 260.87, 389.45 and 219.86 is: 328.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    260.87 : 389.45 = 219.86 : x
  2. Step 2: Convert to fraction form
    260.87/389.45 = 219.86/x
  3. Step 3: Cross multiply
    260.87x = 389.45 × 219.86
  4. Step 4: Simplify right side
    260.87x = 85,621.43
  5. Step 5: Solve for x
    x = 85,621.43/260.87
  6. Step 6: Final answer
    x = 328.22

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.