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Finding the Fourth Proportional to 380.89, 525.54 and 256.78

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Solution

The fourth proportional to 380.89, 525.54 and 256.78 is: 354.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.89 : 525.54 = 256.78 : x
  2. Step 2: Convert to fraction form
    380.89/525.54 = 256.78/x
  3. Step 3: Cross multiply
    380.89x = 525.54 × 256.78
  4. Step 4: Simplify right side
    380.89x = 134,948.16
  5. Step 5: Solve for x
    x = 134,948.16/380.89
  6. Step 6: Final answer
    x = 354.30

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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.