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Finding the Fourth Proportional to 378.25, 521.96 and 210.20

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Solution

The fourth proportional to 378.25, 521.96 and 210.20 is: 290.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.25 : 521.96 = 210.20 : x
  2. Step 2: Convert to fraction form
    378.25/521.96 = 210.20/x
  3. Step 3: Cross multiply
    378.25x = 521.96 × 210.20
  4. Step 4: Simplify right side
    378.25x = 109,715.99
  5. Step 5: Solve for x
    x = 109,715.99/378.25
  6. Step 6: Final answer
    x = 290.06

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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.