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Finding the Fourth Proportional to 71.48, 98.70 and 56.99

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Solution

The fourth proportional to 71.48, 98.70 and 56.99 is: 78.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.48 : 98.70 = 56.99 : x
  2. Step 2: Convert to fraction form
    71.48/98.70 = 56.99/x
  3. Step 3: Cross multiply
    71.48x = 98.70 × 56.99
  4. Step 4: Simplify right side
    71.48x = 5,624.91
  5. Step 5: Solve for x
    x = 5,624.91/71.48
  6. Step 6: Final answer
    x = 78.69

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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.