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Finding the Fourth Proportional to 738.40, 1,019.28 and 660.64

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Solution

The fourth proportional to 738.40, 1,019.28 and 660.64 is: 911.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    738.40 : 1,019.28 = 660.64 : x
  2. Step 2: Convert to fraction form
    738.40/1,019.28 = 660.64/x
  3. Step 3: Cross multiply
    738.40x = 1,019.28 × 660.64
  4. Step 4: Simplify right side
    738.40x = 673,377.14
  5. Step 5: Solve for x
    x = 673,377.14/738.40
  6. Step 6: Final answer
    x = 911.94

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1.5x scale

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.