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Finding the Fourth Proportional to 771.40, 1,065.28 and 660.23

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Solution

The fourth proportional to 771.40, 1,065.28 and 660.23 is: 911.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    771.40 : 1,065.28 = 660.23 : x
  2. Step 2: Convert to fraction form
    771.40/1,065.28 = 660.23/x
  3. Step 3: Cross multiply
    771.40x = 1,065.28 × 660.23
  4. Step 4: Simplify right side
    771.40x = 703,329.81
  5. Step 5: Solve for x
    x = 703,329.81/771.40
  6. Step 6: Final answer
    x = 911.76

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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.