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Finding the Fourth Proportional to 88.70, 121.60 and 87.29

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Solution

The fourth proportional to 88.70, 121.60 and 87.29 is: 119.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.70 : 121.60 = 87.29 : x
  2. Step 2: Convert to fraction form
    88.70/121.60 = 87.29/x
  3. Step 3: Cross multiply
    88.70x = 121.60 × 87.29
  4. Step 4: Simplify right side
    88.70x = 10,613.86
  5. Step 5: Solve for x
    x = 10,613.86/88.70
  6. Step 6: Final answer
    x = 119.66

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.