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Finding the Fourth Proportional to 802.20, 1,203.06 and 640.20

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Solution

The fourth proportional to 802.20, 1,203.06 and 640.20 is: 960.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    802.20 : 1,203.06 = 640.20 : x
  2. Step 2: Convert to fraction form
    802.20/1,203.06 = 640.20/x
  3. Step 3: Cross multiply
    802.20x = 1,203.06 × 640.20
  4. Step 4: Simplify right side
    802.20x = 770,199.01
  5. Step 5: Solve for x
    x = 770,199.01/802.20
  6. Step 6: Final answer
    x = 960.11

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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.