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Finding the Fourth Proportional to 280.76, 387.50 and 170.21

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Solution

The fourth proportional to 280.76, 387.50 and 170.21 is: 234.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.76 : 387.50 = 170.21 : x
  2. Step 2: Convert to fraction form
    280.76/387.50 = 170.21/x
  3. Step 3: Cross multiply
    280.76x = 387.50 × 170.21
  4. Step 4: Simplify right side
    280.76x = 65,956.49
  5. Step 5: Solve for x
    x = 65,956.49/280.76
  6. Step 6: Final answer
    x = 234.93

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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.