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Finding the Fourth Proportional to 505.86, 757.72 and 407.80

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Solution

The fourth proportional to 505.86, 757.72 and 407.80 is: 610.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.86 : 757.72 = 407.80 : x
  2. Step 2: Convert to fraction form
    505.86/757.72 = 407.80/x
  3. Step 3: Cross multiply
    505.86x = 757.72 × 407.80
  4. Step 4: Simplify right side
    505.86x = 308,998.22
  5. Step 5: Solve for x
    x = 308,998.22/505.86
  6. Step 6: Final answer
    x = 610.84

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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.