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Finding the Fourth Proportional to 661.40, 991.20 and 468.80

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Solution

The fourth proportional to 661.40, 991.20 and 468.80 is: 702.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.40 : 991.20 = 468.80 : x
  2. Step 2: Convert to fraction form
    661.40/991.20 = 468.80/x
  3. Step 3: Cross multiply
    661.40x = 991.20 × 468.80
  4. Step 4: Simplify right side
    661.40x = 464,674.56
  5. Step 5: Solve for x
    x = 464,674.56/661.40
  6. Step 6: Final answer
    x = 702.56

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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.