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Finding the Fourth Proportional to 505, 696.90 and 308.59

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Solution

The fourth proportional to 505, 696.90 and 308.59 is: 425.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    505 : 696.90 = 308.59 : x
  2. Step 2: Convert to fraction form
    505/696.90 = 308.59/x
  3. Step 3: Cross multiply
    505x = 696.90 × 308.59
  4. Step 4: Simplify right side
    505x = 215,056.37
  5. Step 5: Solve for x
    x = 215,056.37/505
  6. Step 6: Final answer
    x = 425.85

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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.