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Finding the Fourth Proportional to 378.95, 521.78 and 335.21

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Solution

The fourth proportional to 378.95, 521.78 and 335.21 is: 461.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.95 : 521.78 = 335.21 : x
  2. Step 2: Convert to fraction form
    378.95/521.78 = 335.21/x
  3. Step 3: Cross multiply
    378.95x = 521.78 × 335.21
  4. Step 4: Simplify right side
    378.95x = 174,901.59
  5. Step 5: Solve for x
    x = 174,901.59/378.95
  6. Step 6: Final answer
    x = 461.55

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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.