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Finding the Fourth Proportional to 287.50, 430.90 and 171.70

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Solution

The fourth proportional to 287.50, 430.90 and 171.70 is: 257.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.50 : 430.90 = 171.70 : x
  2. Step 2: Convert to fraction form
    287.50/430.90 = 171.70/x
  3. Step 3: Cross multiply
    287.50x = 430.90 × 171.70
  4. Step 4: Simplify right side
    287.50x = 73,985.53
  5. Step 5: Solve for x
    x = 73,985.53/287.50
  6. Step 6: Final answer
    x = 257.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.