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Finding the Fourth Proportional to 680.80, 939.69 and 570.10

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Solution

The fourth proportional to 680.80, 939.69 and 570.10 is: 786.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.80 : 939.69 = 570.10 : x
  2. Step 2: Convert to fraction form
    680.80/939.69 = 570.10/x
  3. Step 3: Cross multiply
    680.80x = 939.69 × 570.10
  4. Step 4: Simplify right side
    680.80x = 535,714.42
  5. Step 5: Solve for x
    x = 535,714.42/680.80
  6. Step 6: Final answer
    x = 786.89

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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.