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Finding the Fourth Proportional to 505.90, 757.48 and 428.44

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Solution

The fourth proportional to 505.90, 757.48 and 428.44 is: 641.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.90 : 757.48 = 428.44 : x
  2. Step 2: Convert to fraction form
    505.90/757.48 = 428.44/x
  3. Step 3: Cross multiply
    505.90x = 757.48 × 428.44
  4. Step 4: Simplify right side
    505.90x = 324,534.73
  5. Step 5: Solve for x
    x = 324,534.73/505.90
  6. Step 6: Final answer
    x = 641.50

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.