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Finding the Fourth Proportional to 287.80, 394.31 and 283.75

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Solution

The fourth proportional to 287.80, 394.31 and 283.75 is: 388.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.80 : 394.31 = 283.75 : x
  2. Step 2: Convert to fraction form
    287.80/394.31 = 283.75/x
  3. Step 3: Cross multiply
    287.80x = 394.31 × 283.75
  4. Step 4: Simplify right side
    287.80x = 111,885.46
  5. Step 5: Solve for x
    x = 111,885.46/287.80
  6. Step 6: Final answer
    x = 388.76

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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.