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Finding the Fourth Proportional to 505.60, 680.40 and 505.60

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Solution

The fourth proportional to 505.60, 680.40 and 505.60 is: 680.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.60 : 680.40 = 505.60 : x
  2. Step 2: Convert to fraction form
    505.60/680.40 = 505.60/x
  3. Step 3: Cross multiply
    505.60x = 680.40 × 505.60
  4. Step 4: Simplify right side
    505.60x = 344,010.24
  5. Step 5: Solve for x
    x = 344,010.24/505.60
  6. Step 6: Final answer
    x = 680.40

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Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.