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Finding the Fourth Proportional to 287.95, 396.74 and 256.87

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Solution

The fourth proportional to 287.95, 396.74 and 256.87 is: 353.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.95 : 396.74 = 256.87 : x
  2. Step 2: Convert to fraction form
    287.95/396.74 = 256.87/x
  3. Step 3: Cross multiply
    287.95x = 396.74 × 256.87
  4. Step 4: Simplify right side
    287.95x = 101,909.32
  5. Step 5: Solve for x
    x = 101,909.32/287.95
  6. Step 6: Final answer
    x = 353.91

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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.