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Finding the Fourth Proportional to 661.39, 991.81 and 199.02

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Solution

The fourth proportional to 661.39, 991.81 and 199.02 is: 298.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.39 : 991.81 = 199.02 : x
  2. Step 2: Convert to fraction form
    661.39/991.81 = 199.02/x
  3. Step 3: Cross multiply
    661.39x = 991.81 × 199.02
  4. Step 4: Simplify right side
    661.39x = 197,390.03
  5. Step 5: Solve for x
    x = 197,390.03/661.39
  6. Step 6: Final answer
    x = 298.45

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.