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Finding the Fourth Proportional to 688.54, 949.96 and 393.70

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Solution

The fourth proportional to 688.54, 949.96 and 393.70 is: 543.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.54 : 949.96 = 393.70 : x
  2. Step 2: Convert to fraction form
    688.54/949.96 = 393.70/x
  3. Step 3: Cross multiply
    688.54x = 949.96 × 393.70
  4. Step 4: Simplify right side
    688.54x = 373,999.25
  5. Step 5: Solve for x
    x = 373,999.25/688.54
  6. Step 6: Final answer
    x = 543.18

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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.