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Finding the Fourth Proportional to 640.90, 960.90 and 294.40

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Solution

The fourth proportional to 640.90, 960.90 and 294.40 is: 441.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.90 : 960.90 = 294.40 : x
  2. Step 2: Convert to fraction form
    640.90/960.90 = 294.40/x
  3. Step 3: Cross multiply
    640.90x = 960.90 × 294.40
  4. Step 4: Simplify right side
    640.90x = 282,888.96
  5. Step 5: Solve for x
    x = 282,888.96/640.90
  6. Step 6: Final answer
    x = 441.39

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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.