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Finding the Fourth Proportional to 287.81, 397.19 and 199.31

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Solution

The fourth proportional to 287.81, 397.19 and 199.31 is: 275.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.81 : 397.19 = 199.31 : x
  2. Step 2: Convert to fraction form
    287.81/397.19 = 199.31/x
  3. Step 3: Cross multiply
    287.81x = 397.19 × 199.31
  4. Step 4: Simplify right side
    287.81x = 79,162.20
  5. Step 5: Solve for x
    x = 79,162.20/287.81
  6. Step 6: Final answer
    x = 275.05

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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.