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Finding the Fourth Proportional to 309.88, 427.22 and 299.80

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Solution

The fourth proportional to 309.88, 427.22 and 299.80 is: 413.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.88 : 427.22 = 299.80 : x
  2. Step 2: Convert to fraction form
    309.88/427.22 = 299.80/x
  3. Step 3: Cross multiply
    309.88x = 427.22 × 299.80
  4. Step 4: Simplify right side
    309.88x = 128,080.56
  5. Step 5: Solve for x
    x = 128,080.56/309.88
  6. Step 6: Final answer
    x = 413.32

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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.