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Finding the Fourth Proportional to 71.70, 98.86 and 61.36

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Solution

The fourth proportional to 71.70, 98.86 and 61.36 is: 84.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.70 : 98.86 = 61.36 : x
  2. Step 2: Convert to fraction form
    71.70/98.86 = 61.36/x
  3. Step 3: Cross multiply
    71.70x = 98.86 × 61.36
  4. Step 4: Simplify right side
    71.70x = 6,066.05
  5. Step 5: Solve for x
    x = 6,066.05/71.70
  6. Step 6: Final answer
    x = 84.60

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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.