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Finding the Fourth Proportional to 287.32, 395.70 and 285.70

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Solution

The fourth proportional to 287.32, 395.70 and 285.70 is: 393.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.32 : 395.70 = 285.70 : x
  2. Step 2: Convert to fraction form
    287.32/395.70 = 285.70/x
  3. Step 3: Cross multiply
    287.32x = 395.70 × 285.70
  4. Step 4: Simplify right side
    287.32x = 113,051.49
  5. Step 5: Solve for x
    x = 113,051.49/287.32
  6. Step 6: Final answer
    x = 393.47

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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.