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Finding the Fourth Proportional to 650, 979.88 and 640.28

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Solution

The fourth proportional to 650, 979.88 and 640.28 is: 965.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    650 : 979.88 = 640.28 : x
  2. Step 2: Convert to fraction form
    650/979.88 = 640.28/x
  3. Step 3: Cross multiply
    650x = 979.88 × 640.28
  4. Step 4: Simplify right side
    650x = 627,397.57
  5. Step 5: Solve for x
    x = 627,397.57/650
  6. Step 6: Final answer
    x = 965.23

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.