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Finding the Fourth Proportional to 287.58, 396.72 and 274.80

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Solution

The fourth proportional to 287.58, 396.72 and 274.80 is: 379.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.58 : 396.72 = 274.80 : x
  2. Step 2: Convert to fraction form
    287.58/396.72 = 274.80/x
  3. Step 3: Cross multiply
    287.58x = 396.72 × 274.80
  4. Step 4: Simplify right side
    287.58x = 109,018.66
  5. Step 5: Solve for x
    x = 109,018.66/287.58
  6. Step 6: Final answer
    x = 379.09

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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.