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Finding the Fourth Proportional to 86.70, 129.95 and 61.03

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Solution

The fourth proportional to 86.70, 129.95 and 61.03 is: 91.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.70 : 129.95 = 61.03 : x
  2. Step 2: Convert to fraction form
    86.70/129.95 = 61.03/x
  3. Step 3: Cross multiply
    86.70x = 129.95 × 61.03
  4. Step 4: Simplify right side
    86.70x = 7,930.93
  5. Step 5: Solve for x
    x = 7,930.93/86.70
  6. Step 6: Final answer
    x = 91.47

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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.