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Finding the Fourth Proportional to 389.66, 537.80 and 256.65

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Solution

The fourth proportional to 389.66, 537.80 and 256.65 is: 354.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.66 : 537.80 = 256.65 : x
  2. Step 2: Convert to fraction form
    389.66/537.80 = 256.65/x
  3. Step 3: Cross multiply
    389.66x = 537.80 × 256.65
  4. Step 4: Simplify right side
    389.66x = 138,026.37
  5. Step 5: Solve for x
    x = 138,026.37/389.66
  6. Step 6: Final answer
    x = 354.22

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.