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Finding the Fourth Proportional to 71.80, 98.85 and 62.98

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Solution

The fourth proportional to 71.80, 98.85 and 62.98 is: 86.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.80 : 98.85 = 62.98 : x
  2. Step 2: Convert to fraction form
    71.80/98.85 = 62.98/x
  3. Step 3: Cross multiply
    71.80x = 98.85 × 62.98
  4. Step 4: Simplify right side
    71.80x = 6,225.57
  5. Step 5: Solve for x
    x = 6,225.57/71.80
  6. Step 6: Final answer
    x = 86.71

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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.