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Finding the Fourth Proportional to 779.50, 1,170.11 and 389.39

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Solution

The fourth proportional to 779.50, 1,170.11 and 389.39 is: 584.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.50 : 1,170.11 = 389.39 : x
  2. Step 2: Convert to fraction form
    779.50/1,170.11 = 389.39/x
  3. Step 3: Cross multiply
    779.50x = 1,170.11 × 389.39
  4. Step 4: Simplify right side
    779.50x = 455,630.11
  5. Step 5: Solve for x
    x = 455,630.11/779.50
  6. Step 6: Final answer
    x = 584.52

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Double scale
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1.5x scale

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.