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Finding the Fourth Proportional to 380.57, 525.08 and 287.09

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Solution

The fourth proportional to 380.57, 525.08 and 287.09 is: 396.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.57 : 525.08 = 287.09 : x
  2. Step 2: Convert to fraction form
    380.57/525.08 = 287.09/x
  3. Step 3: Cross multiply
    380.57x = 525.08 × 287.09
  4. Step 4: Simplify right side
    380.57x = 150,741.16
  5. Step 5: Solve for x
    x = 150,741.16/380.57
  6. Step 6: Final answer
    x = 396.10

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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.