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Finding the Fourth Proportional to 505.89, 698.56 and 309.47

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Solution

The fourth proportional to 505.89, 698.56 and 309.47 is: 427.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.89 : 698.56 = 309.47 : x
  2. Step 2: Convert to fraction form
    505.89/698.56 = 309.47/x
  3. Step 3: Cross multiply
    505.89x = 698.56 × 309.47
  4. Step 4: Simplify right side
    505.89x = 216,179.10
  5. Step 5: Solve for x
    x = 216,179.10/505.89
  6. Step 6: Final answer
    x = 427.32

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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.