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Finding the Fourth Proportional to 505.20, 696.80 and 298.20

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Solution

The fourth proportional to 505.20, 696.80 and 298.20 is: 411.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.20 : 696.80 = 298.20 : x
  2. Step 2: Convert to fraction form
    505.20/696.80 = 298.20/x
  3. Step 3: Cross multiply
    505.20x = 696.80 × 298.20
  4. Step 4: Simplify right side
    505.20x = 207,785.76
  5. Step 5: Solve for x
    x = 207,785.76/505.20
  6. Step 6: Final answer
    x = 411.29

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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.