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Finding the Fourth Proportional to 284.30, 428.24 and 258.78

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Solution

The fourth proportional to 284.30, 428.24 and 258.78 is: 389.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.30 : 428.24 = 258.78 : x
  2. Step 2: Convert to fraction form
    284.30/428.24 = 258.78/x
  3. Step 3: Cross multiply
    284.30x = 428.24 × 258.78
  4. Step 4: Simplify right side
    284.30x = 110,818.65
  5. Step 5: Solve for x
    x = 110,818.65/284.30
  6. Step 6: Final answer
    x = 389.80

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.