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Finding the Fourth Proportional to 688.60, 950.31 and 393.80

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Solution

The fourth proportional to 688.60, 950.31 and 393.80 is: 543.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.60 : 950.31 = 393.80 : x
  2. Step 2: Convert to fraction form
    688.60/950.31 = 393.80/x
  3. Step 3: Cross multiply
    688.60x = 950.31 × 393.80
  4. Step 4: Simplify right side
    688.60x = 374,232.08
  5. Step 5: Solve for x
    x = 374,232.08/688.60
  6. Step 6: Final answer
    x = 543.47

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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.