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Finding the Fourth Proportional to 287.18, 430.75 and 70.75

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Solution

The fourth proportional to 287.18, 430.75 and 70.75 is: 106.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.18 : 430.75 = 70.75 : x
  2. Step 2: Convert to fraction form
    287.18/430.75 = 70.75/x
  3. Step 3: Cross multiply
    287.18x = 430.75 × 70.75
  4. Step 4: Simplify right side
    287.18x = 30,475.56
  5. Step 5: Solve for x
    x = 30,475.56/287.18
  6. Step 6: Final answer
    x = 106.12

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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.