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Finding the Fourth Proportional to 505.20, 756.86 and 288.12

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Solution

The fourth proportional to 505.20, 756.86 and 288.12 is: 431.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.20 : 756.86 = 288.12 : x
  2. Step 2: Convert to fraction form
    505.20/756.86 = 288.12/x
  3. Step 3: Cross multiply
    505.20x = 756.86 × 288.12
  4. Step 4: Simplify right side
    505.20x = 218,065.06
  5. Step 5: Solve for x
    x = 218,065.06/505.20
  6. Step 6: Final answer
    x = 431.64

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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.