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Finding the Fourth Proportional to 378.12, 521.81 and 210.07

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Solution

The fourth proportional to 378.12, 521.81 and 210.07 is: 289.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.12 : 521.81 = 210.07 : x
  2. Step 2: Convert to fraction form
    378.12/521.81 = 210.07/x
  3. Step 3: Cross multiply
    378.12x = 521.81 × 210.07
  4. Step 4: Simplify right side
    378.12x = 109,616.63
  5. Step 5: Solve for x
    x = 109,616.63/378.12
  6. Step 6: Final answer
    x = 289.90

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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.