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Finding the Fourth Proportional to 578.80, 811.40 and 578.80

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Solution

The fourth proportional to 578.80, 811.40 and 578.80 is: 811.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    578.80 : 811.40 = 578.80 : x
  2. Step 2: Convert to fraction form
    578.80/811.40 = 578.80/x
  3. Step 3: Cross multiply
    578.80x = 811.40 × 578.80
  4. Step 4: Simplify right side
    578.80x = 469,638.32
  5. Step 5: Solve for x
    x = 469,638.32/578.80
  6. Step 6: Final answer
    x = 811.40

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Double scale
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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.