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Finding the Fourth Proportional to 688.78, 950.50 and 378.28

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Solution

The fourth proportional to 688.78, 950.50 and 378.28 is: 522.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.78 : 950.50 = 378.28 : x
  2. Step 2: Convert to fraction form
    688.78/950.50 = 378.28/x
  3. Step 3: Cross multiply
    688.78x = 950.50 × 378.28
  4. Step 4: Simplify right side
    688.78x = 359,555.14
  5. Step 5: Solve for x
    x = 359,555.14/688.78
  6. Step 6: Final answer
    x = 522.02

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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.