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Finding the Fourth Proportional to 2,101, 3,151.48 and 640.20

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Solution

The fourth proportional to 2,101, 3,151.48 and 640.20 is: 960.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,101 : 3,151.48 = 640.20 : x
  2. Step 2: Convert to fraction form
    2,101/3,151.48 = 640.20/x
  3. Step 3: Cross multiply
    2,101x = 3,151.48 × 640.20
  4. Step 4: Simplify right side
    2,101x = 2,017,577.50
  5. Step 5: Solve for x
    x = 2,017,577.50/2,101
  6. Step 6: Final answer
    x = 960.29

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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.