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Finding the Fourth Proportional to 688.36, 949.99 and 393.72

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Solution

The fourth proportional to 688.36, 949.99 and 393.72 is: 543.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.36 : 949.99 = 393.72 : x
  2. Step 2: Convert to fraction form
    688.36/949.99 = 393.72/x
  3. Step 3: Cross multiply
    688.36x = 949.99 × 393.72
  4. Step 4: Simplify right side
    688.36x = 374,030.06
  5. Step 5: Solve for x
    x = 374,030.06/688.36
  6. Step 6: Final answer
    x = 543.36

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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.