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Finding the Fourth Proportional to 287.64, 393.48 and 286.47

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Solution

The fourth proportional to 287.64, 393.48 and 286.47 is: 391.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.64 : 393.48 = 286.47 : x
  2. Step 2: Convert to fraction form
    287.64/393.48 = 286.47/x
  3. Step 3: Cross multiply
    287.64x = 393.48 × 286.47
  4. Step 4: Simplify right side
    287.64x = 112,720.22
  5. Step 5: Solve for x
    x = 112,720.22/287.64
  6. Step 6: Final answer
    x = 391.88

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.