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Finding the Fourth Proportional to 378.32, 521.51 and 253.70

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Solution

The fourth proportional to 378.32, 521.51 and 253.70 is: 349.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.32 : 521.51 = 253.70 : x
  2. Step 2: Convert to fraction form
    378.32/521.51 = 253.70/x
  3. Step 3: Cross multiply
    378.32x = 521.51 × 253.70
  4. Step 4: Simplify right side
    378.32x = 132,305.11
  5. Step 5: Solve for x
    x = 132,305.11/378.32
  6. Step 6: Final answer
    x = 349.72

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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.