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Finding the Fourth Proportional to 853.50, 1,279.30 and 784.30

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Solution

The fourth proportional to 853.50, 1,279.30 and 784.30 is: 1,175.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    853.50 : 1,279.30 = 784.30 : x
  2. Step 2: Convert to fraction form
    853.50/1,279.30 = 784.30/x
  3. Step 3: Cross multiply
    853.50x = 1,279.30 × 784.30
  4. Step 4: Simplify right side
    853.50x = 1,003,354.99
  5. Step 5: Solve for x
    x = 1,003,354.99/853.50
  6. Step 6: Final answer
    x = 1,175.58

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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.