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Finding the Fourth Proportional to 688.90, 950.64 and 378.40

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Solution

The fourth proportional to 688.90, 950.64 and 378.40 is: 522.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.90 : 950.64 = 378.40 : x
  2. Step 2: Convert to fraction form
    688.90/950.64 = 378.40/x
  3. Step 3: Cross multiply
    688.90x = 950.64 × 378.40
  4. Step 4: Simplify right side
    688.90x = 359,722.18
  5. Step 5: Solve for x
    x = 359,722.18/688.90
  6. Step 6: Final answer
    x = 522.17

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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.