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Finding the Fourth Proportional to 661.67, 991.90 and 250.70

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Solution

The fourth proportional to 661.67, 991.90 and 250.70 is: 375.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.67 : 991.90 = 250.70 : x
  2. Step 2: Convert to fraction form
    661.67/991.90 = 250.70/x
  3. Step 3: Cross multiply
    661.67x = 991.90 × 250.70
  4. Step 4: Simplify right side
    661.67x = 248,663.74
  5. Step 5: Solve for x
    x = 248,663.74/661.67
  6. Step 6: Final answer
    x = 375.82

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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.