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Finding the Fourth Proportional to 378.05, 521.70 and 212.25

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Solution

The fourth proportional to 378.05, 521.70 and 212.25 is: 292.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.05 : 521.70 = 212.25 : x
  2. Step 2: Convert to fraction form
    378.05/521.70 = 212.25/x
  3. Step 3: Cross multiply
    378.05x = 521.70 × 212.25
  4. Step 4: Simplify right side
    378.05x = 110,730.83
  5. Step 5: Solve for x
    x = 110,730.83/378.05
  6. Step 6: Final answer
    x = 292.90

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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.