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Finding the Fourth Proportional to 10.50, 15.68 and 8.78

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Solution

The fourth proportional to 10.50, 15.68 and 8.78 is: 13.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.50 : 15.68 = 8.78 : x
  2. Step 2: Convert to fraction form
    10.50/15.68 = 8.78/x
  3. Step 3: Cross multiply
    10.50x = 15.68 × 8.78
  4. Step 4: Simplify right side
    10.50x = 137.67
  5. Step 5: Solve for x
    x = 137.67/10.50
  6. Step 6: Final answer
    x = 13.11

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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.