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Finding the Fourth Proportional to 8.70, 13 and 6.99

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Solution

The fourth proportional to 8.70, 13 and 6.99 is: 10.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.70 : 13 = 6.99 : x
  2. Step 2: Convert to fraction form
    8.70/13 = 6.99/x
  3. Step 3: Cross multiply
    8.70x = 13 × 6.99
  4. Step 4: Simplify right side
    8.70x = 90.87
  5. Step 5: Solve for x
    x = 90.87/8.70
  6. Step 6: Final answer
    x = 10.44

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.