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Finding the Fourth Proportional to 779.90, 1,169.85 and 259.94

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Solution

The fourth proportional to 779.90, 1,169.85 and 259.94 is: 389.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.90 : 1,169.85 = 259.94 : x
  2. Step 2: Convert to fraction form
    779.90/1,169.85 = 259.94/x
  3. Step 3: Cross multiply
    779.90x = 1,169.85 × 259.94
  4. Step 4: Simplify right side
    779.90x = 304,090.81
  5. Step 5: Solve for x
    x = 304,090.81/779.90
  6. Step 6: Final answer
    x = 389.91

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Similar ratio
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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.