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Finding the Fourth Proportional to 280.90, 421.35 and 159.17

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Solution

The fourth proportional to 280.90, 421.35 and 159.17 is: 238.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.90 : 421.35 = 159.17 : x
  2. Step 2: Convert to fraction form
    280.90/421.35 = 159.17/x
  3. Step 3: Cross multiply
    280.90x = 421.35 × 159.17
  4. Step 4: Simplify right side
    280.90x = 67,065.95
  5. Step 5: Solve for x
    x = 67,065.95/280.90
  6. Step 6: Final answer
    x = 238.75

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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.