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Finding the Fourth Proportional to 847.75, 1,170.38 and 640.39

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Solution

The fourth proportional to 847.75, 1,170.38 and 640.39 is: 884.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    847.75 : 1,170.38 = 640.39 : x
  2. Step 2: Convert to fraction form
    847.75/1,170.38 = 640.39/x
  3. Step 3: Cross multiply
    847.75x = 1,170.38 × 640.39
  4. Step 4: Simplify right side
    847.75x = 749,499.65
  5. Step 5: Solve for x
    x = 749,499.65/847.75
  6. Step 6: Final answer
    x = 884.10

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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.