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Finding the Fourth Proportional to 380.98, 525.71 and 215.20

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Solution

The fourth proportional to 380.98, 525.71 and 215.20 is: 296.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.98 : 525.71 = 215.20 : x
  2. Step 2: Convert to fraction form
    380.98/525.71 = 215.20/x
  3. Step 3: Cross multiply
    380.98x = 525.71 × 215.20
  4. Step 4: Simplify right side
    380.98x = 113,129.09
  5. Step 5: Solve for x
    x = 113,129.09/380.98
  6. Step 6: Final answer
    x = 296.94

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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.