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Finding the Fourth Proportional to 309.88, 427.50 and 308.50

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Solution

The fourth proportional to 309.88, 427.50 and 308.50 is: 425.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.88 : 427.50 = 308.50 : x
  2. Step 2: Convert to fraction form
    309.88/427.50 = 308.50/x
  3. Step 3: Cross multiply
    309.88x = 427.50 × 308.50
  4. Step 4: Simplify right side
    309.88x = 131,883.75
  5. Step 5: Solve for x
    x = 131,883.75/309.88
  6. Step 6: Final answer
    x = 425.60

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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.