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Finding the Fourth Proportional to 159.79, 239.70 and 87.65

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Solution

The fourth proportional to 159.79, 239.70 and 87.65 is: 131.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    159.79 : 239.70 = 87.65 : x
  2. Step 2: Convert to fraction form
    159.79/239.70 = 87.65/x
  3. Step 3: Cross multiply
    159.79x = 239.70 × 87.65
  4. Step 4: Simplify right side
    159.79x = 21,009.71
  5. Step 5: Solve for x
    x = 21,009.71/159.79
  6. Step 6: Final answer
    x = 131.48

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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.