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Finding the Fourth Proportional to 287.79, 397.29 and 188.31

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Solution

The fourth proportional to 287.79, 397.29 and 188.31 is: 259.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.79 : 397.29 = 188.31 : x
  2. Step 2: Convert to fraction form
    287.79/397.29 = 188.31/x
  3. Step 3: Cross multiply
    287.79x = 397.29 × 188.31
  4. Step 4: Simplify right side
    287.79x = 74,813.68
  5. Step 5: Solve for x
    x = 74,813.68/287.79
  6. Step 6: Final answer
    x = 259.96

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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.