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Finding the Fourth Proportional to 688.63, 950.31 and 378.13

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Solution

The fourth proportional to 688.63, 950.31 and 378.13 is: 521.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.63 : 950.31 = 378.13 : x
  2. Step 2: Convert to fraction form
    688.63/950.31 = 378.13/x
  3. Step 3: Cross multiply
    688.63x = 950.31 × 378.13
  4. Step 4: Simplify right side
    688.63x = 359,340.72
  5. Step 5: Solve for x
    x = 359,340.72/688.63
  6. Step 6: Final answer
    x = 521.82

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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.