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Finding the Fourth Proportional to 378.16, 521.40 and 308.07

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Solution

The fourth proportional to 378.16, 521.40 and 308.07 is: 424.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.16 : 521.40 = 308.07 : x
  2. Step 2: Convert to fraction form
    378.16/521.40 = 308.07/x
  3. Step 3: Cross multiply
    378.16x = 521.40 × 308.07
  4. Step 4: Simplify right side
    378.16x = 160,625.09
  5. Step 5: Solve for x
    x = 160,625.09/378.16
  6. Step 6: Final answer
    x = 424.76

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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.